Communication system and methods for fully implantable modular cochlear implant system

ABSTRACT

Cochlear implant systems can include a cochlear electrode, a stimulator in electrical communication with the cochlear electrode, and a signal processor in communication with the stimulator. The signal processor can include circuitry and a can surrounding and housing the circuitry. The signal processor can further include a first impedance between the circuitry and the can in order to reduce unintended electrical communication between the cochlear electrode and the circuitry of the signal processor. Other components can similarly include impedance between their respective cans and circuitry to prevent such undesired communication. Components can communicate with one another via bidirectional communication. Communication can include communication of signals and inverted signals to reduce net charge flow through the wearer&#39;s body.

CROSS-REFERENCES AND PRIORITY CLAIM

This application claims priority to U.S. Provisional Patent ApplicationNo. 62/376,195 and U.S. Provisional Patent Application No. 62/376,198,each of which was filed Aug. 17, 2016, and is incorporated herein byreference in its entirety

BACKGROUND

A cochlear implant is an electronic device that may be at leastpartially implanted surgically into the cochlea, the hearing organ ofthe inner ear, to provide improved hearing to a patient. Cochlearimplants may include components that are worn externally by the patientand components that are implanted internally in the patient.

External components may include a microphone, a processor, and atransmitter. Cochlear implants may detect sounds via an ear levelmicrophone that conveys these sounds to a wearable processor. Someprocessors may be worn behind the patient's ear. An electronic signalfrom the processor may be sent to a transmission coil worn externallybehind the ear over the implant. The transmission coil may send a signalto the implant receiver, located under the patient's scalp.

Internal components may include a receiver and one or more electrodes.Some cochlear implants may include additional processing circuitry amongthe internal components. The receiver may direct signals to one or moreelectrodes that have been implanted within the cochlea. The responses tothese signals may then be conveyed along the auditory nerve to thecortex of the brain where they are interpreted as sound.

Some cochlear implants may be fully implanted and include a mechanismfor measuring sound similar to a microphone, signal processingelectronics, and means for directing signals to one or more electrodesimplanted within the cochlea. Fully implanted cochlear implantstypically do not include a transmission coil or a receiver coil.

Internal components of such cochlear implant systems typically requireelectrical power to operate. Thus, a power supply is typically includedalong with the other internal components. However, performance of suchpower supplies often degrades over time, and the power supply mayrequire replacement. Additionally, processing circuitry technologycontinues to advance quickly. Improvements to processing technology overtime may render the processing technology in the implanted processingcircuitry outdated. Thus, there may be times when it is advantageous toreplace/upgrade the processing circuitry.

However, such replacement procedures can be difficult. The location ofthe implanted internal components is not the most amenable to surgicalprocedures, and tends not to fully heal after many incisions.Additionally, replacement of some components, such as a signalprocessor, can require removing and reintroducing components such aselectrical leads into the patient's cochlear tissue, which can bedamaging to the tissue and negatively impact the efficacy of cochlearstimulation.

Additionally, different challenges exist for communicating electricalsignals through a patient's body. For example, safety standards canlimit the amount of current that can safely flow through a patient'sbody (particularly DC current). Additionally, the patient's body can actas an undesired signal path between different components within the body(e.g., via contact with the housing or “can” of each component). Thiscan lead to reduced signal strength and/or undesired communication orinterference between components. In some cases, electrical signals mayeven stimulate undesired regions of the patient's cochlear tissue,interfering with the efficacy of the cochlear implant.

SUMMARY

Some aspects of this disclosure are generally directed toward cochlearimplant systems and communication between components thereof. Exemplarycochlear implant systems include a cochlear electrode, a stimulator inelectrical communication with the cochlear electrode, and a signalprocessor in communication with the stimulator. The signal processor caninclude a circuitry, a can surrounding and housing the circuitry, and afirst impedance between the circuitry and the can to reduce unintendedelectrical communication between the cochlear electrode and thecircuitry of the signal processor.

Similarly, the system can include an implantable battery and/orcommunication module configured to provide electrical power to thesignal processor. The implantable battery and/or communication modulecan similarly include circuitry and a can surrounding and housing thecircuitry. The implantable battery and/or communication module caninclude a second impedance between the circuitry and the can to reduceunintended electrical communication between the cochlear electrode andthe circuitry of the implantable battery and/or communication module.

Other system components can similarly include impedances to reduce theunintended electrical communication between the cochlear electrode andthe circuitry of such components. This can improve the efficiency andaccuracy of electrical signals applied from the cochlear electrode tothe cochlear tissue rather than leaking signals from the cochlearelectrode to various system components via the body. Impedances cangenerally include various components, such as one or more resistors,capacitors, inductors, etc. In some examples, impedances can include anopen circuit.

In some examples, communication between implantable components (e.g., asignal processor and an implantable battery and/or communication module)can be configured such that a signal and its inverse are communicatedthrough the wearer's body. For example, an implantable battery and/orcommunication module can include a signal generator configured togenerate electrical signals for communication to the signal processorand an inverting amplifier in communication with the signal generatorand configured to output inverted electrical signals. The implantablebattery and/or communication module can be configured to provideelectrical signals and inverted electrical signals to the signalprocessor via a first lead. Such communication can be configured so thatzero net charge flows between components.

In some such embodiments, a signal processor can include a rectifiercircuit configured to receive the signals and the inverse signals andproduce a substantially DC electrical output. Thus, power can similarlybe transferred between the implantable battery and/or communicationmodule and the signal processor while minimizing the net charge flowingbetween the components. Capacitive couplings can be included in variouscommunication interfaces to prevent DC signals from flowing betweenvarious components.

This disclosure is filed concurrently with the following patentapplications that are owned by the owner of this disclosure: U.S. patentapplication Ser. No. 15/679,755, titled “FULLY IMPLANTABLE MODULARCOCHLEAR IMPLANT SYSTEM,” U.S. patent application Ser. No. 15/679,768,titled “COMMUNICATION SYSTEM AND METHODS FOR FULLY IMPLANTABLE MODULARCOCHLEAR IMPLANT SYSTEM,” and PCT Patent Application No. PCT/US17/47354,titled “IMPLANTABLE MODULAR COCHLEAR IMPLANT SYSTEM WITH COMMUNICATIONSYSTEM AND NETWORK,” each of which is hereby incorporated into thisdisclosure by reference in their entirety

The details of one or more examples are set forth in the accompanyingdrawings and the description below. Other features, objects, andadvantages will be apparent from the description and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a schematic illustration of a fully implantable cochlearimplant system.

FIG. 2 shows an embodiment of a fully-implantable cochlear implant.

FIGS. 3A and 3B are exemplary illustrations showing communication withthe signal processor.

FIGS. 4 and 5 illustrate embodiments of an exemplary middle ear sensorfor use in conjunction with anatomical features of a patient.

FIG. 6 shows an illustration of an exemplary detachable connector.

FIG. 7 shows an exemplary cochlear implant system in a patient that isnot fully physically developed, such as a child.

FIG. 8 is a process-flow diagram illustrating an exemplary process forinstalling and/or updating an implantable cochlear implant system into apatient.

FIG. 9 is a schematic diagram illustrating an exemplary implantablesystem including an acoustic stimulator.

FIG. 10A is a high level electrical schematic showing communicationbetween the implantable battery and/or communication module and thesignal processor.

FIG. 10B illustrates an exemplary schematic diagram illustrating acochlear electrode having a plurality of contact electrodes and fixedlyor detachably connected to an electrical stimulator.

FIG. 11A shows a high level schematic diagram illustrating an exemplarycommunication configuration between an implantable battery and/orcommunication module, a signal processor, and a stimulator in anexemplary cochlear implant system.

FIG. 11B is a schematic diagram illustrating exemplary electricalcommunication between an implantable battery and/or communication moduleand a signal processor in a cochlear implant system according to someembodiments.

FIG. 12A is an alternative high-level schematic diagram illustrating anexemplary communication configuration between an implantable batteryand/or communication module, a signal processor, and a stimulator.

FIG. 12B is an alternative schematic diagram illustrating exemplaryelectrical communication between an implantable battery and/orcommunication module and a signal processor in a cochlear implant systemsimilar to that shown in FIG. 12A.

FIG. 12C is another alternative schematic diagram illustrating exemplaryelectrical communication between an implantable battery and/orcommunication module and a signal processor in a cochlear implant systemsimilar to that shown in FIG. 12A.

FIG. 13 is a process flow diagram illustrating an exemplary process forestablishing a preferred transfer function for a patient.

FIG. 14 is a process flow diagram illustrating an exemplary process forestablishing a preferred transfer function for a patient.

FIG. 15 is a process flow diagram showing an exemplary method of testingthe efficacy of one or more sounds using one or more transfer functionsvia pre-processed signals.

FIG. 16 is a schematic representation of an exemplary database ofpre-processed sound signals.

FIG. 17 is a schematic diagram illustrating possible communicationbetween a variety of system components according to some embodiments ofa fully-implantable system.

FIG. 18 is a chart showing the various parameters that are adjustable byeach of a variety of external devices.

DETAILED DESCRIPTION

FIG. 1 shows a schematic illustration of a fully implantable cochlearimplant system. The system of FIG. 1 includes a middle ear sensor 110 incommunication with a signal processor 120. The middle ear sensor 110 canbe configured to detect incoming sound waves, for example, using the earstructure of a patient. The signal processor 120 can be configured toreceive a signal from the middle ear sensor 110 and produce an outputsignal based thereon. For example, the signal processor 120 can beprogrammed with instructions to output a certain signal based on areceived signal. In some embodiments, the output of the signal processor120 can be calculated using an equation based on received input signals.Alternatively, in some embodiments, the output of the signal processor120 can be based on a lookup table or other programmed (e.g., in memory)correspondence between the input signal from the middle ear sensor 110and the output signal. While not necessarily based explicitly on afunction, the relationship between the input to the signal processor 120(e.g., from the middle ear sensor 110) and the output of the signalprocessor 120 is referred to as the transfer function of the signalprocessor 120.

The system of FIG. 1 further includes a cochlear electrode 116 implantedinto the cochlear tissues of a patient. The cochlear electrode 116 is inelectrical communication with an electrical stimulator 130, which can beconfigured to provide electrical signals to the cochlear electrode 116in response to input signals received by the electrical stimulator 130.In some examples, the cochlear electrode 116 is fixedly attached to theelectrical stimulator 130. In other examples, the cochlear electrode 116is removably attached to the electrical stimulator 130. As shown, theelectrical stimulator 130 is in communication with the signal processor120. In some embodiments, the electrical stimulator 130 provideselectrical signals to the cochlear electrode 116 based on output signalsfrom the signal processor 120.

In various embodiments, the cochlear electrode 116 can include anynumber of contact electrodes in electrical contact with different partsof the cochlear tissue. In such embodiments, the electrical stimulator130 can be configured to provide electrical signals to any number ofsuch contact electrodes to stimulate the cochlear tissue. For example,in some embodiments, the electrical stimulator 130 is configured toactivate different contact electrodes or combinations of contactelectrodes of the cochlear electrode 116 in response to different inputsignals received from the signal processor 120. This can help thepatient differentiate between different input signals.

During exemplary operation, the middle ear sensor 110 detects audiosignals, for example, using features of the patient's ear anatomy asdescribed elsewhere herein and in U.S. Patent Publication No.2013/0018216, which is hereby incorporated by reference in its entirety.The signal processor 120 can receive such signals from the middle earsensor 110 and produce an output to the electrical stimulator 130 basedon the transfer function of the signal processor 120. The electricalstimulator 130 can then stimulate one or more contact electrodes of thecochlear electrode 116 based on the received signals from the signalprocessor 120.

Referring to FIG. 2, an embodiment of a fully-implantable cochlearimplant is shown. The device in this embodiment includes a processor 220(e.g., signal processor), a sensor 210, a first lead 270 connecting thesensor 210 to the processor 220, and a combination lead 280 attached tothe processor 220, wherein combination lead 280 contains both a groundelectrode 217 and a cochlear electrode 216. The illustrated processor220 includes a housing 202, a coil 208, first female receptacle 271 andsecond female receptacle 281 for insertion of the leads 270 and 280,respectively.

In some embodiments, coil 208 can receive power and/or data from anexternal device, for instance, including a transmission coil (notshown). Some such examples are described in U.S. Patent Publication No.2013/0018216, which is incorporated by reference. In other examples,processor 220 is configured to receive power and/or data from othersources, such as an implantable battery and/or communication module asshown in FIG. 1. Such battery and/or communication module can beimplanted, for example, into the pectoral region of the patient in orderto provide adequate room for larger equipment (e.g., a relatively largebattery) for prolonged operation (e.g., longer battery life).Additionally, in the event a battery needs eventual replacement, areplacement procedure in the patient's pectoral region can be performedseveral times without certain vascularization issues that can arise nearthe location of the cochlear implant. For example, in some cases,repeated procedures (e.g., battery replacement) near the cochlearimplant can result in a decreased ability for the skin in the region toheal after a procedure. Placing a replaceable component such as abattery in the pectoral region can facilitate replacement procedureswith reduced risk for such issues.

FIGS. 3A and 3B are exemplary illustrations showing communication with asignal processor. For example, referring to FIGS. 3A and 3B, theprocessor 320, includes a housing 302, a coil 308, and a generic lead380 are shown. The lead 380 is removable and can be attached to theprocessor 320 by insertion of a male connector 382 of the generic lead380 into any available female receptacle, shown here as 371 or 381. FIG.3A shows the processor 320 with the generic lead 380 removed. FIG. 3Bshows the processor 320 with the generic lead 380 attached. The maleconnector 382 is exchangeable, and acts as a seal to prevent or minimizefluid transfer into the processor 320.

FIGS. 4 and 5 illustrate embodiments of an exemplary middle ear sensorfor use in conjunction with anatomical features of a patient. Referringto FIG. 4, an embodiment of the sensor 410 of a fully-implantablecochlear implant is shown. Here, the sensor 410 is touching the malleus422. The sensor may include a cantilever 432 within a sensor housing434. The sensor 410 may be in communication with the processor 420 by atleast two wires 436 and 438, which may form a first lead (e.g., 270).Both wires can be made of biocompatible materials, but need notnecessarily be the same biocompatible material. Examples of suchbiocompatible materials can include tungsten, platinum, palladium, andthe like. In various embodiments, one, both, or neither of wires 436 and438 are coated with a coating and/or disposed inside a casing, such asdescribed in U.S. Patent Publication No. 2013/0018216, which isincorporated by reference.

The illustrated cantilever 432 includes at least two ends, where atleast one end is in operative contact with the tympanic membrane or oneor more bones of the ossicular chain. The cantilever 432 may be alaminate of at least two layers of material. The material used may bepiezoelectric. One example of such a cantilever 432 is a piezoelectricbimorph, which is well-known in the art (see for example, U.S. Pat. No.5,762,583). In one embodiment, the cantilever is made of two layers ofpiezoelectric material. In another embodiment, the cantilever is made ofmore than two layers of piezoelectric material. In yet anotherembodiment, the cantilever is made of more than two layers ofpiezoelectric material and non-piezoelectric material.

The sensor housing 434 of the sensor 410 may be made of a biocompatiblematerial. In one embodiment, the biocompatible material may be titaniumor gold. In another embodiment, the sensor 410 may be similar to thesensor described in U.S. Pat. No. 7,524,278 to Madsen et al., oravailable sensors, such as that used in the ESTEEM™ implant (EnvoyMedical, Corp., St. Paul, Minn.), for example. In alternativeembodiments, the sensor 410 may be an electromagnetic sensor, an opticalsensor, or an accelerometer. Accelerometers are known in the art, forexample, as described in U.S. Pat. No. 5,540,095.

Referring to FIG. 5, an embodiment of the sensor 510 of afully-implantable cochlear implant is shown. Also shown are portions ofthe subject's anatomy, which includes, if the subject is anatomicallynormal, at least the malleus 522, incus 524, and stapes 526 of themiddle ear 528, and the cochlea 548, oval window 546, and round window544 of the inner ear 542. Here, the sensor 510 is touching the incus524. The sensor 510 in this embodiment can be as described for theembodiment of sensor 410 shown in FIG. 4. Further, although not shown ina drawing, the sensor 510 may be in operative contact with the tympanicmembrane or the stapes, or any combination of the tympanic membrane,malleus 522, incus 524, or stapes 526.

FIGS. 4 and 5 illustrate an exemplary middle ear sensor for use withsystems described herein. However, other middle ear sensors can be used,such as sensors using microphones or other sensors capable of receivingan input corresponding to detected sound and outputting a correspondingsignal to the signal processor. Additionally or alternatively, systemscan include other sensors configured to output a signal representativeof sound received at or near a user's ear, such as a microphone or otheracoustic pickup located in the user's outer ear or implanted under theuser's skin. Such devices may function as an input source, for example,to the signal processor such that the signal processor receives an inputsignal from the input source and generates and output one or morestimulation signals according to the received input signal and thesignal processor transfer function.

Referring back to FIG. 1, the signal processor 120 is shown as being incommunication with the middle ear sensor 110, the electrical stimulator130, and the implantable battery and/or communication module 140. Asdescribed elsewhere herein, the signal processor 120 can receive inputsignals from the middle ear sensor 110 and/or other input source(s) andoutput signals to the electrical stimulator 130 for stimulating thecochlear electrode 116. The signal processor 120 can receive data (e.g.,processing data establishing or updating the transfer function of thesignal processor 120) and/or power from the implantable battery and/orcommunication module 140. In some embodiments, the signal processor 120can communicate with such components via inputs such as those shown inFIG. 3.

In some embodiments, the implantable battery and/or communication module140 can communicate with external components, such as a programmer 100and/or a battery charger 102. The battery charger 102 can wirelesslycharge the battery in the implantable battery and/or communicationmodule 140 when brought into proximity with the implantable batteryand/or communication module 140 in the pectoral region of the patient.Such charging can be accomplished, for example, using inductivecharging. The programmer 100 can be configured to wirelessly communicatewith the implantable battery and/or communication module 140 via anyappropriate wireless communication technology, such as Bluetooth, Wi-Fi,and the like. In some examples, the programmer 100 can be used to updatethe system firmware and/or software. In an exemplary operation, theprogrammer 100 can be used to communicate an updated signal processor120 transfer function to the implantable battery and/or communicationmodule 140. In various embodiments, the programmer 100 and charger 102can be separate devices or can be integrated into a single device.

In the illustrated example of FIG. 1, the signal processor 120 isconnected to the middle ear sensor 110 via lead 170. In someembodiments, lead 170 can provide communication between the signalprocessor 120 and the middle ear sensor 110. In some embodiments, lead170 can include a plurality of isolated conductors providing a pluralityof communication channels between the middle ear sensor 110 and thesignal processor 120. The lead 170 can include a coating such as anelectrically insulating sheath to minimize any conduction of electricalsignals to the body of the patient.

In various embodiments, one or more communication leads can bedetachable such that communication between two components can bedisconnected in order to electrically and/or mechanically separate suchcomponents. For instance, in some embodiments, lead 170 includes adetachable connector 171. Detachable connector 171 can facilitatedecoupling of the signal processor 120 and middle ear sensor 110. FIG. 6shows an illustration of an exemplary detachable connector. In theillustrated example, the detachable connector 671 includes a maleconnector 672 and a female connector 673. In the illustrated example,the male connector 672 includes a plurality of isolated electricalcontacts 682 and female connector 673 includes a corresponding pluralityof electrical contacts 683. When the male connector 672 is inserted intothe female connector 673, contacts 682 make electrical contact withcontacts 683. Each corresponding pair of contacts 682, 683 can provide aseparate channel of communication between components connected via thedetachable connector 671. In the illustrated example, four channels ofcommunication are possible, but it will be appreciated that any numberof communication channels are possible. Additionally, while shown asindividual circumferentially extending contacts 683, otherconfigurations are possible.

In some embodiments, male 672 and female 673 connectors are attached atthe end of leads 692, 693, respectively. Such leads can extend fromcomponents of the implantable cochlear system. For example, withreference to FIG. 1, in some embodiments, lead 170 can include a firstlead extending from the middle ear sensor 110 having one of a male(e.g., 672) or a female (e.g., 673) connector and a second leadextending from the signal processor 120 having the other of the male orfemale connector. The first and second leads can be connected atdetachable connector 171 in order to facilitate communication betweenthe middle ear sensor 110 and the signal processor 120.

In other examples, a part of the detachable connector 171 can beintegrated into one of the middle ear sensor 110 and the signalprocessor 120 (e.g., as shown in FIG. 3). For example, in an exemplaryembodiment, the signal processor 120 can include a female connector(e.g., 673) integrated into a housing of the signal processor 120. Lead170 can extend fully from the middle ear sensor 110 and terminate at acorresponding male connector (e.g., 672) for inserting into the femaleconnector of the signal processor 120. In still further embodiments, alead (e.g., 170) can include connectors on each end configured todetachably connect with connectors integrated into each of thecomponents in communication. For example, lead 170 can include two maleconnectors, two female connectors, or one male and one female connectorfor detachably connecting with corresponding connectors integral to themiddle ear sensor 110 and the signal processor 120. Thus, lead 170 mayinclude two or more detachable connectors.

Similar communication configurations can be established for detachableconnector 181 of lead 180 facilitating communication between the signalprocessor 120 and the stimulator 130 and for detachable connector 191 oflead 190 facilitating communication between the signal processor 120 andthe implantable battery and/or communication module 140. Leads (170,180, 190) can include pairs of leads having corresponding connectorsextending from each piece of communicating equipment, or connectors canbe built in to any one or more communicating components.

In such configurations, each of the electrical stimulator 130, signalprocessor 120, middle ear sensor 110, and battery and/or communicationmodule can each be enclosed in a housing, such as a hermetically sealedhousing comprising biocompatible materials. Such components can includefeedthroughs providing communication to internal components enclosed inthe housing. Feedthroughs can provide electrical communication to thecomponent via leads extending from the housing and/or connectorsintegrated into the components.

In a module configuration such as that shown in FIG. 1, variouscomponents can be accessed (e.g., for upgrades, repair, replacement,etc.) individually from other components. For example, as signalprocessor 120 technology improves (e.g., improvements in size,processing speed, power consumption, etc.), the signal processor 120implanted as part of the system can be removed and replacedindependently of other components. In an exemplary procedure, animplanted signal processor 120 can be disconnected from the electricalstimulator 130 by disconnecting detachable connector 181, from themiddle ear sensor 110 by disconnecting detachable connector 171, andfrom the implantable battery and/or communication module 140 bydisconnecting detachable connector 191. Thus, the signal processor 120can be removed from the patient while other components such as theelectrical stimulator 130, cochlear electrode 116, middle ear sensor110, and battery and/or communication module can remain in place in thepatient.

After the old signal processor is removed, a new signal processor can beconnected to the electrical stimulator 130, middle ear sensor 110, andimplantable battery and/or communication module 140 via detachableconnectors 181, 171, and 191, respectively. Thus, the signal processor(e.g., 120) can be replaced, repaired, upgraded, or any combinationthereof, without affecting the other system components. This can reduce,among other things, the risk, complexity, duration, and recovery time ofsuch a procedure. In particular, the cochlear electrode 116 can be leftin place in the patient's cochlea while other system components can beadjusted, reducing trauma to the patient's cochlear tissue.

Such modularity of system components can be particularly advantageouswhen replacing a signal processor 120, such as described above.Processor technology continues to improve, and will likely continue tomarkedly improve in the future, making the signal processor 120 a likelycandidate for significant upgrades and/or replacement during thepatient's lifetime. Additionally, in embodiments such as the embodimentshown in FIG. 1, the signal processor 120 communicates with many systemcomponents. For example, as shown, the signal processor 120 is incommunication with each of the electrical stimulator 130, the middle earsensor 110, and the implantable battery and/or communication module 140.Detachably connecting such components with the signal processor 120(e.g., via detachable connectors 181, 171, and 191) enables replacementof the signal processor 120 without disturbing any other components.Thus, in the event of an available signal processor 120 upgrade and/or afailure of the signal processor 120, the signal processor 120 can bedisconnected from other system components and removed.

While many advantages exist for a replaceable signal processor 120, themodularity of other system components can be similarly advantageous, forexample, for upgrading any system component. Similarly, if a systemcomponent (e.g., the middle ear sensor 110) should fail, the componentcan be disconnected from the rest of the system (e.g., via detachableconnector 171) and replaced without disturbing the remaining systemcomponents. In another example, even a rechargeable battery included inthe implantable battery and/or communication module 140 may eventuallywear out and need replacement. The implantable battery and/orcommunication module 140 can be replaced or accessed (e.g., forreplacing the battery) without disturbing other system components.Further, as discussed elsewhere herein, when the implantable batteryand/or communication module 140 is implanted in the pectoral region ofthe patient, such as in the illustrated example, such a procedure canleave the patient's head untouched, eliminating unnecessarily frequentaccess beneath the skin.

While various components are described herein as being detachable, invarious embodiments, one or more components configured to communicatewith one another can be integrated into a single housing. For example,in some embodiments, signal processor 120 can be integrally formed withthe stimulator 130 and cochlear electrode 116. For example, in anexemplary embodiment, processing and stimulation circuitry of a signalprocessor 120 and stimulator 130 can be integrally formed as a singleunit in a housing coupled to a cochlear electrode. Cochlear electrodeand the signal processor/stimulator can be implanted during an initialprocedure and operate as a single unit.

In some embodiments, while the integral signalprocessor/stimulator/cochlear electrode component does not get removedfrom a patient due to potential damage to the cochlear tissue into whichthe cochlear electrode is implanted, system upgrades are still possible.For example, in some embodiments, a module signal processor may beimplanted alongside the integral signal processor/stimulator componentand communicate therewith. In some such examples, the integral signalprocessor may include a built-in bypass to allow a later-implantedsignal processor to interface directly with the stimulator. Additionallyor alternatively, the modular signal processor can communicate with theintegral signal processor, which may be programmed with a unity transferfunction. Thus, in some such embodiments, signals from the modularsignal processor may be essentially passed through the integral signalprocessor unchanged so that the modular signal processor effectivelycontrols action of the integral stimulator. Thus, in variousembodiments, hardware and/or software solutions exist for upgrading anintegrally attached signal processor that may be difficult or dangerousto remove.

Another advantage to a modular cochlear implant system such as shown inFIG. 1 is the ability to implant different system components into apatient at different times. For example, infants and children aretypically not suited for a fully implantable system such as shown inFIG. 1. Instead, such patients typically are candidates to wear atraditional cochlear implant system. For example, FIG. 7 shows anexemplary cochlear implant system in a patient that is not fullyphysically developed, such as a child. The system includes a cochlearelectrode 716 implanted into the cochlear tissue of the patient. Thecochlear electrode 716 of FIG. 7 can include many of the properties ofthe cochlear electrodes described herein. The cochlear electrode 716 canbe in electrical communication with an electrical stimulator 730, whichcan be configured to stimulate portions of the cochlear electrode 716 inresponse to an input signal, such as described elsewhere herein. Theelectrical stimulator 730 can receive input signals from a signalprocessor 720.

In some cases, components such as a middle ear sensor are incompatiblewith a patient who is not fully physically developed. For example,various dimensions within a growing patient's anatomy, such as spacingbetween anatomical structures or between locations on anatomicalstructures (e.g., equipment attachment points) may change as the patientgrows, thereby potentially rendering a middle ear sensor that isextremely sensitive to motion ineffective. Similarly, the undevelopedpatient may not be able to support the implantable battery and/orcommunication module. Thus, the signal processor 720 can be incommunication with a communication device for communicating withcomponents external to the patient. Such communication components caninclude, for example, a coil 708, shown as being connected to the signalprocessor 720 via lead 770. The coil 708 can be used to receive dataand/or power from devices external to the user. For example, microphoneor other audio sensing device (not shown) can be in communication withan external coil 709 configured to transmit data to the coil 708implanted in the patient. Similarly, a power source (e.g., a battery)can be coupled to an external coil 709 and configured to provide powerto the implanted components via the implanted coil 708. Additionally,processing data (e.g., updates to the signal processor 720 transferfunction) can also be communicated to the implanted coil 708 from anexternal coil 709. While generally discussed using coil 708, it will beappreciated that communication between external and implanted components(e.g., the signal processor 720) can be performed using othercommunication technology, such as various forms of wirelesscommunication. As shown, in the embodiment of FIG. 7, the signalprocessor 720 is coupled to the coil 708 via lead 770 and detachableconnector 771. Accordingly, the coil 708 can be detached from the signalprocessor 720 and removed without disrupting the signal processor 720.

When a patient has become fully developed, for example, to the pointthat the patient can safely accommodate a middle ear sensor and animplantable battery and/or communication module, the coil 708 can beremoved and remaining components of the fully implantable system can beimplanted. That is, once a patient is developed, the cochlear implantsystem (e.g., of FIG. 7) can be updated to a fully implantable cochlearimplant system (e.g., of FIG. 1). In some examples, the patient isconsidered sufficiently developed once the patient reaches age 18 oranother predetermined age. Additional or alternative criteria may beused, such as when various anatomical sizes or determined developmentalstates are achieved.

FIG. 8 is a process-flow diagram illustrating an exemplary process forinstalling and/or updating an implantable cochlear implant system into apatient. A cochlear electrode can be implanted in communication with thepatient's cochlear tissue and an electrical stimulator can be implantedin communication with the cochlear electrode (850). A signal processorcan be implanted into the patient (852). As described elsewhere herein,the signal processor can be connected to the electrical stimulator via adetachable connector (854). In examples in which the signal processor isintegrally formed with one or more components, such as the stimulatorand cochlear electrode, steps 850, 852, and 854 can be combined into asingle step comprising implanting the cochlear electrode, stimulator,and signal processor component.

If, at the time of implementing the process of FIG. 8, it can bedetermined if the patient is considered sufficiently developed (856). Ifnot, a coil (or other communication device) such as described withrespect to FIG. 7 can be implanted (858). The coil can be connected tothe signal processor via the detachable connector (860), and thecochlear implant can operate in conjunction with external components(862), such as microphones and external power supplies and coils.

However, if a patient is, or has become, sufficiently developed (856),additional components can be implanted into the patient. For example,the method can include implanting a middle ear sensor (864) andconnecting the middle ear sensor to the signal processor via adetachable connector (866). Additionally, the method can includeimplanting a battery and/or communication module (868) and connectingthe battery and/or communication module to the signal processor via adetachable connector (870). If the patient had become sufficientlydeveloped after having worn a partially external device such as thatdescribed with respect to FIG. 7 and steps 858-862, the method caninclude removing various components that had been previously implanted.For example, a coil, such as implanted in step 858, can be disconnectedand removed during the procedure of implanting the middle ear sensor(864).

The process of FIG. 8 can be embodied in a method of fitting a patientwith an implantable hearing system. Such a method can include implantinga first system (e.g., the system of FIG. 7) into a patient at a firstage. This can include, for example, performing steps 850-562 in FIG. 8.The method can further include, when the patient reaches a second age,the second age being greater than the first, removing some components ofthe first system (e.g., a coil) and implanting the not-yet implantedcomponents of second system (e.g., the system of FIG. 1), for example,via steps 864-870 of FIG. 8.

Transitioning from the system of FIG. 7 to the system of FIG. 1, forexample, via the process of FIG. 8, can have several advantages. From apatient preference standpoint, some patients may prefer a system that istotally implanted and requires no wearable external components.Additionally, an implanted battery and/or communication module incommunication with the signal processor via lead 190 (and detachableconnector 191) can much more efficiently relay power and/or data to thesignal processor when compared to an external device such as a coil.

Such modular systems provide distinct advantages over previousimplantable or partially implantable cochlear implant systems.Generally, previous systems include several components included into asingle housing implanted into the patient. For example, functionality ofa signal processor, electrical stimulator, and sensor can be enclosed ina single, complex component. If any such aspects of the component fail,which becomes more likely as the complexity increases, the entire modulemust be replaced. By contrast, in a modular system, such as shown inFIG. 1, individual components can be replaced while leaving others inplace. Additionally, such systems including, for example, coil-to-coilpower and/or data communication through the patient's skin alsogenerally communicate less efficiently than an internal connection suchas via the lead 190. Modular systems such as shown in FIGS. 1 and 7 alsoallow for a smooth transition from a partially implantable system for apatient who is not yet fully developed and a fully implantable systemonce the patient has become fully developed.

While often described herein as using an electrical stimulator tostimulate the patient's cochlear tissue via a cochlear electrode, insome examples, the system can additionally or alternatively include anacoustic stimulator. An acoustic stimulator can include, for example, atransducer (e.g., a piezoelectric transducer) configured to providemechanical stimulation to the patient's ear structure. In an exemplaryembodiment, the acoustic stimulator can be configured to stimulate oneor more portions of the patient's ossicular chain via amplifiedvibrations. Acoustic stimulators can include any appropriate acousticstimulators, such as those found in the ESTEEM™ implant (Envoy MedicalCorp., St. Paul, Minn.) or as described in U.S. Pat. Nos. 4,729,366,4,850,962, and 7,524,278, and U.S. Patent Publication No. 20100042183,each of which is incorporated herein by reference in its entirety.

FIG. 9 is a schematic diagram illustrating an exemplary implantablesystem including an acoustic stimulator. The acoustic stimulator can beimplanted proximate the patient's ossicular chain and can be incommunication with a signal processor via lead 194 and detachableconnector 195. The signal processor can behave as described elsewhereherein, and can be configured to cause acoustic stimulation of theossicular chain via the acoustic stimulator in in response to inputsignals from the middle ear sensor according to a transfer function ofthe signal processor.

The acoustic stimulator of FIG. 9 can be used similarly to theelectrical stimulator as described elsewhere herein. For instance, anacoustic stimulator can be mechanically coupled to a patient's ossicularchain upon implanting the system, and coupled to the signal processorvia lead 194 and detachable connector 195. Similarly to systemsdescribed elsewhere herein with respect to the electrical stimulator, ifthe signal processor requires replacement or repair, the signalprocessor can be disconnected from the acoustic stimulator (viadetachable connector 195) so that the signal processor can be removedwithout disturbing the acoustic stimulator.

In general, systems incorporating an acoustic sensor such as shown inFIG. 9 can operate in the same way as systems described elsewhere hereinemploying an electrical stimulator and cochlear electrode onlysubstituting electrical stimulation for acoustic stimulation. The samemodularity benefits, including system maintenance and upgrades as wellas the ability to convert to a fully implantable system when a patientbecomes sufficiently developed, can be similarly realized using acousticstimulation systems. For example, the process illustrated in FIG. 8 canbe performed in an acoustic stimulation system simply by substitutingthe electrical stimulator and cochlear electrode for an acousticstimulator.

Some systems can include a hybrid system comprising both an electricalstimulator and an acoustic stimulator in communication with the signalprocessor. In some such examples, the signal processor can be configuredto stimulate electrically and/or acoustically according to the transferfunction of the signal processor. In some examples, the type ofstimulation used can depend on the input signal received by the signalprocessor. For instance, in an exemplary embodiment, the frequencycontent of the input signal to the signal processor can dictate the typeof stimulation. In some cases, frequencies below a threshold frequencycould be represented using one of electrical and acoustic stimulationwhile frequencies above the threshold frequency could be representedusing the other of electrical and acoustic stimulation. Such a thresholdfrequency could be adjustable based on the hearing profile of thepatient. Using a limited range of frequencies can reduce the number offrequency domains, and thus the number of contact electrodes, on thecochlear electrode. In other examples, rather than a single thresholdfrequency defining which frequencies are stimulated electrically andacoustically, various frequencies can be stimulated both electricallyand acoustically. In some such examples, the relative amount ofelectrical and acoustic stimulation can be frequency-dependent. Asdescribed elsewhere herein, the signal processor transfer function canbe updated to meet the needs of the patient, including the electricaland acoustic stimulation profiles.

With further reference to FIGS. 1 and 9, in some examples, a system caninclude a shut-off controller 104, which can be configured to wirelesslystop an electrical stimulator 130 from stimulating the patient'scochlear tissue and/or an acoustic stimulator 150 from stimulating thepatient's ossicular chain. For example, if the system is malfunctioningor an uncomfortably loud input sound causes an undesirable level ofstimulation, the user may use the shut-off controller 104 to ceasestimulation from the stimulator 130. The shut-off controller 104 can beembodied in a variety of ways. For example, in some embodiments, theshut-off controller 104 can be integrated into other externalcomponents, such as the programmer 100. In some such examples, theprogrammer 100 includes a user interface by which a user can select anemergency shut-off feature to cease stimulation. Additionally oralternatively, the shut-off controller 104 can be embodied as a separatecomponent. This can be useful in situations in which the patient may nothave immediate access to the programmer 100. For example, the shut-offcontroller 104 can be implemented as a wearable component that thepatient can wear at all or most times, such as a ring, bracelet,necklace, or the like.

The shut-off controller 104 can communicate with the system in order tostop stimulation in a variety of ways. In some examples, the shut-offcontroller 104 comprises a magnet that is detectable by a sensor (e.g.,a Hall-Effect sensor) implanted in the patient, such as in the processorand/or the implantable battery and/or communication module 140. In somesuch embodiments, when the magnet is brought sufficiently close to thesensor, the system can stop stimulation of the cochlear tissue orossicular chain.

After the shut-off controller 104 is used to disable stimulation,stimulation can be re-enabled in one or more of a variety of ways. Forexample, in some embodiments, stimulation is re-enabled after apredetermined amount of time after it had been disabled. In otherexamples, the shut-off controller 104 can be used to re-enablestimulation. In some such examples, the patient brings the shut-offcontroller 104 within a first distance of a sensor (e.g., a magneticsensor) to disable stimulation, and then removes the shut-off controller104. Subsequently, once the patient brings the shut-off controller 104within a second distance of the sensor, stimulation can be re-enabled.In various embodiments, the first distance can be less than the seconddistance, equal to the second distance, or greater than the seconddistance. In still further embodiments, another device such as aseparate turn-on controller (not shown) or the programmer 100 can beused to re-enable stimulation. Any combination of such re-enabling ofstimulation can be used, such as alternatively using either theprogrammer 100 or the shut-off controller 104 to enable stimulation orcombining a minimum “off” time before any other methods can be used tore-enable stimulation.

In some embodiments, rather than entirely disable stimulation, otheractions can be taken, such as reducing the magnitude of stimulation. Forexample, in some embodiments, the shut-off sensor can be used to reducethe signal output by a predetermined amount (e.g., absolute amount,percentage, etc.). In other examples, the shut-off sensor can affect thetransfer function of the signal processor to reduce the magnitude ofstimulation in a customized way, such as according to frequency or otherparameter of an input signal (e.g., from the middle ear sensor).

With reference back to FIG. 1, as described elsewhere herein, theimplantable battery and/or communication module can be used to providepower and/or data (e.g., processing instructions) to other systemcomponents via lead 190. Different challenges exist for communicatingelectrical signals through a patient's body. For example, safetystandards can limit the amount of current that can safely flow through apatient's body (particularly DC current). Additionally, the patient'sbody can act as an undesired signal path from component to component(e.g., via contact with the housing or “can” of each component). Varioussystems and methods can be employed to improve the communication abilitybetween system components.

FIG. 10A is a high level electrical schematic showing communicationbetween the implantable battery and/or communication module and thesignal processor. In the illustrated embodiment, the implantable batteryand/or communication module includes circuitry in communication withcircuitry in the signal processor. Communication between the circuitryin the implantable battery and/or communication module and the signalprocessor can be facilitated by a lead (190), represented by the leadtransfer function. The lead transfer function can include, for example,parasitic resistances and capacitances between the leads connecting theimplantable battery and/or communication module and the signal processorand the patient's body and/or between two or more conductors that makeup the lead (e.g., 191). Signals communicated from the circuitry of theimplantable battery and/or communication module to the circuitry in thesignal processor can include electrical power provided to operate and/orstimulate system components (e.g., the middle ear sensor, signalprocessor, electrical and/or acoustic stimulator, and/or cochlearelectrode) and/or data (e.g., processing data regarding the transferfunction of the signal processor).

As discussed elsewhere herein, the body of the patient provides anelectrical path between system components, such as the “can” of theimplantable battery and/or communication module and the “can” of thesignal processor. This path is represented in FIG. 10A by the flow paththrough R_(Body). Thus, the patient's body can provide undesirablesignal paths which can negatively impact communication betweencomponents. To address this, in some embodiments, operating circuitry ineach component can be substantially isolated from the component “can”and thus the patient's body. For example, as shown, resistance R_(Can)is positioned between the circuitry and the “can” of both theimplantable battery and/or communication module and the signalprocessor.

While being shown as R_(Can) in each of the implantable battery and/orcommunication module and the signal processor, it will be appreciatedthat the actual value of the resistance between the circuitry andrespective “can” of different elements is not necessarily equal.Additionally, R_(Can) need not include purely a resistance, but caninclude other components, such as one or more capacitors, inductors, andthe like. That is, R_(Can) can represent an insulating circuit includingany variety of components that act to increase the impedance betweencircuitry within a component and the “can” of the component. Thus,R_(Can) can represent an impedance between the operating circuitry of acomponent and the respective “can” and the patient's tissue. Isolatingthe circuitry from the “can” and the patient's body acts to similarlyisolate the circuitry from the “can” of other components, allowing eachcomponent to operate with reference to a substantially isolatedcomponent ground. This can eliminate undesired communication andinterference between system components and/or between system componentsand the patient's body.

For example, as described elsewhere herein, in some examples, anelectrical stimulator can provide an electrical stimulus to one or morecontact electrodes on a cochlear electrode implanted in a patient'scochlear tissue. FIG. 10B illustrates an exemplary schematic diagramillustrating a cochlear electrode having a plurality of contactelectrodes and fixedly or detachably connected to an electricalstimulator. As shown, the cochlear electrode 1000 has four contactelectrodes 1002, 1004, 1006, and 1008, though it will be appreciatedthat any number of contact electrodes is possible. As describedelsewhere herein, the electrical stimulator can provide electricalsignals to one or more such contact electrodes in response to an outputfrom the signal processor according to the transfer function thereof anda received input signal.

Because each contact electrode 1002-1008 is in contact with thepatient's cochlear tissue, each is separated from the “can” of theelectrical stimulator (as well as the “cans” of other system components)via the impedance of the patient's tissue, shown as R_(Body). Thus, ifthe circuitry within various system components did not have sufficientlyhigh impedance (e.g., R_(Can)) to the component “can”, electricalsignals may stimulate undesired regions of the patient's cochleartissue. For instance, stimulation intended for a particular contactelectrode (e.g., 1002) may lead to undesired stimulation of othercontact electrodes (e.g., 1004, 1006, 1008), reducing the overallefficacy of the system. Minimizing the conductive paths between systemcomponents (e.g., to the contact electrodes of a cochlear electrode) dueto the patient's body, such as by incorporating impedances betweencomponent circuitry and the corresponding “can” via R_(Can), cantherefore improve the ability to apply an electrical stimulus to only adesired portion of the patient's body.

It will be appreciated that the term R_(Body) is used herein togenerally represent the resistance and/or impedance of the patient'stissue between various components, and does not refer to a specificvalue. Moreover, each depiction or R_(Body) in the figures does notnecessarily represent the same value of resistance and/or impedance asthe others.

FIG. 11A shows a high level schematic diagram illustrating an exemplarycommunication configuration between an implantable battery and/orcommunication module, a signal processor, and a stimulator. In theexample of FIG. 11A, the implantable battery and/or communication module1110 is in two-way communication with the signal processor 1120. Forinstance, the implantable battery and/or communication module 1110 cancommunicate power and/or data signals 1150 to the signal processor 1120.In some examples, the power and data signals 1150 can be included in asingle signal generated in the implantable battery and/or communicationmodule 1110 and transmitted to the signal processor 1120. Such signalscan include, for example, a digital signal transmitted with a particularclock rate, which in some embodiments, can be adjustable, for example,via the implantable battery and/or communication module 1110.

In some embodiments, the signal processor 1120 can communicateinformation to the implantable battery and/or communication module 1110(e.g., via signals 1151), for example, feedback information and/orrequests for more power, etc. The implantable battery and/orcommunication module 1110 can, in response, adjust its output to thesignal processor 1120 (e.g., an amplitude, duty cycle, clock rate, etc.)in order to accommodate for the received feedback (e.g., to provide morepower, etc.). Thus, in some such examples, the implantable batteryand/or communication module 1110 can communicate power and data (e.g.,via 1150) to the signal processor 1120, and the signal processor 1120can communicate various data back to the implantable battery and/orcommunication module 1110 (e.g., via 1151).

In some embodiments, similar communication can be implemented betweenthe signal processor 1120 and the stimulator 1130, wherein the signalprocessor 1120 provides power and data to the stimulator 1130 (e.g., via1160) and receives data in return from the stimulator 1130 (e.g., via1161). For example, the signal processor 1120 can be configured tooutput signals (e.g., power and/or data) to the stimulator 1130 (e.g.,based on received inputs from a middle ear sensor or other device) via asimilar communication protocol as implemented between the implantablebattery and/or communication module 1110 and the signal processor 1120.Similarly, in some embodiments, the stimulator can be configured toprovide feedback signals to the signal processor, for example,representative of an executed stimulation process. Additionally oralternatively, the stimulator may provide diagnostic information, suchas electrode impedance and neural response telemetry or other biomarkersignals.

FIG. 11B is a schematic diagram illustrating exemplary electricalcommunication between an implantable battery and/or communication moduleand a signal processor in a cochlear implant system according to someembodiments. In the illustrated embodiment, the implantable batteryand/or communication module 1110 includes a signal generator 1112configured to output a signal through a lead (e.g., 190) to the signalprocessor 1120. As described with respect to FIG. 11A, in some examples,the signal generator 1112 is configured to generate both data and powersignals (e.g., 1150) for communication to the signal processor 1120. Insome embodiments, the signal generator 1112 generates a digital signalfor communication to the signal processor 1120. The digital signal fromthe signal generator 1112 can be communicated to the signal processor1120 at a particular clock rate. In some examples, the signals aregenerated at approximately 30 kHz. In various examples, data and powerfrequencies can range from approximately 100 Hz to approximately 10 MHz,and in some examples, may be adjustable, for example, by a user.

In the illustrated embodiment, the implantable battery and/orcommunication module 1110 includes a controller in communication withthe signal generator 1112. In some examples, the controller is capableof adjusting communication parameters such as the clock rate of thesignal generator 1112. In an exemplary embodiment, the controller and/orthe signal generator 1112 can communicate with, for example, a patient'sexternal programmer (e.g., as shown in FIG. 1). The controller and/orsignal generator 1112 can be configured to communicate data to thesignal processor 1120 (e.g., via 1151), such as updated firmware, signalprocessor 1120 transfer functions, or the like.

As shown, the signal generator 1112 outputs the generated signal to anamplifier 1190 and an inverting amplifier 1192. In some examples, bothamplifiers are unity gain amplifiers. In some examples comprisingdigital signals, the inverting amplifier 1192 can comprise a digital NOTgate. The output from the amplifier 1190 and the inverting amplifier1192 are generally opposite one another and are directed to the signalprocessor 1120. In some embodiments, the opposite nature of the signalsoutput to the signal processor 1120 from amplifiers 1190 and 1192results in a charge-neutral communication between the implantablebattery and/or communication module 1110 and the signal processor 1120,such that no net charge flows through the wearer.

In the illustrated example of FIG. 11B, the receiving circuitry in thesignal processor 1120 comprises a rectifier circuit 1122 that receivessignals (e.g., 1150) from the amplifier 1190 and the inverting amplifier1192. Since the output of one of the amplifiers 1190 and 1192 will behigh, the rectifier circuit 1122 can be configured to receive theopposite signals from the amplifiers 1190 and 1192 and generatetherefrom a substantially DC power output 1123. In various embodiments,the DC power 1123 can be used to power a variety of components, such asthe signal processor 1120 itself, the middle ear sensor, the electricaland/or acoustic stimulator, or the like. The rectifier circuit 1122 caninclude any known appropriate circuitry components for rectifying one ormore input signals, such as a diode rectification circuit or atransistor circuit, for example.

As described elsewhere herein, the implantable battery and/orcommunication module 1110 can communicate data to the signal processor1120. In some embodiments, the controller and/or the signal generator1112 is configured to encode the data for transmission via the outputamplifiers 1190 and 1192. The signal processor 1120 can include a signalextraction module 1124 configured to extract the data signal 1125 fromthe signal(s) (e.g., 1150) communicated to the signal processor 1120 toproduce a signal for use by the signal processor 1120. In some examples,the signal extraction module 1124 is capable of decoding the signal thatwas encoded by the implantable battery and/or communication module 1110.Additionally or alternatively, the signal extraction module 1124 canextract a signal 1125 resulting from the lead transfer function. Invarious examples, the extracted signal 1125 can include, for example, anupdated transfer function for the signal processor 1120, a desiredstimulation command, or other signals that affect operation of thesignal processor 1120.

In the illustrated example, the signal processor 1120 includes acontroller 1126 that is capable of monitoring the DC power 1123 and thesignal 1125 received from the implantable battery and/or communicationmodule 1110. The controller 1126 can be configured to analyze thereceived DC power 1123 and the signal 1125 and determine whether or notthe power and/or signal is sufficient. For example, the controller 1126may determine that the signal processor 1120 is receiving insufficientDC power for stimulating a cochlear electrode according to the signalprocessor 1120 transfer function, or that data from the implantablebattery and/or communication module 1110 is not communicated at adesired rate. Thus, in some examples, the controller 1126 of the signalprocessor 1120 can communicate with the controller 1114 of theimplantable battery and/or communication module 1110 and providefeedback regarding the received communication. Based on the receivedfeedback from the controller 1126 of the signal processor 1120, thecontroller 1114 of the implantable battery and/or communication module1110 can adjust various properties of the signal output by theimplantable battery and/or communication module 1110. For example, thecontroller of the implantable battery and/or communication module 1110can adjust the clock rate of the communication from the signal generator1112 to the signal processor 1120.

In some systems, the transmission efficiency between the implantablebattery and/or communication module 1110 and the signal processor 1120is dependent on the clock rate of transmission. Accordingly, in someexamples, the implantable battery and/or communication module 1110begins by transmitting at an optimized clock rate until a change inclock rate is requested via the signal processor 1120, for example, toenhance data transmission (e.g., rate, resolution, etc.). In otherinstances, if more power is required (e.g., the controller of the signalprocessor 1120 determines the DC power is insufficient), the clock ratecan be adjusted to improve transmission efficiency, and thus themagnitude of the signal received at the signal processor 1120. It willbe appreciated that in addition or alternatively to adjusting a clockrate, adjusting an amount of power transmitted to the signal processor1120 can include adjusting the magnitude of the signal output from thesignal generator 1112. In some embodiments, for example, with respect toFIGS. 11A-B, power and data can be communicated, for example, fromimplantable battery and/or communication module 1110 to the signalprocessor 1120 at a rate of approximately 30 kHz, and can be adjustedfrom there as necessary and/or as requested, for example, by the signalprocessor 1120.

FIG. 12A is an alternative high-level schematic diagram illustrating anexemplary communication configuration between an implantable batteryand/or communication module, a signal processor, and a stimulator. Inthe example of FIG. 12A, the implantable battery and/or communicationmodule 1210 provides signals to the signal processor 1220 viacommunication link 1250, and is further in two-way communication withthe signal processor 1220 via communication link 1251. In the example ofFIG. 12A, the implantable battery and/or communication module 1210 canprovide power signals to the signal processor 1220 via communicationlink 1250 and otherwise be in two-way data communication with the signalprocessor 1220 via communication link 1251. In some such examples, thepower and data signals can each include digital signals. However, insome embodiments, the power and data signals are transmitted atdifferent clock rates. In some examples, the clock rate of the datasignals is at least one order of magnitude greater than the clock rateof the power signals. For example, in an exemplary embodiment, the powersignal is communicated at a clock rate of approximately 30 kHz, whilethe data communication occurs at a clock rate of approximately 1 MHz.Similarly to the embodiment described in FIG. 11A, in some examples, theclock rate can be adjustable, for example, via the implantable batteryand/or communication module 1210.

As described with respect to FIG. 11A, in some embodiments, the signalprocessor 1220 can communicate information to the implantable batteryand/or communication module 1210, for example, feedback informationand/or requests for more power, etc. (e.g., via two-way communication1251). The implantable battery and/or communication module 1210 can, inresponse, adjust the power and/or data output to the signal processor1220 (e.g., an amplitude, duty cycle, clock rate, etc.) in order toaccommodate for the received feedback (e.g., to provide more power,etc.).

In some embodiments, similar communication can be implemented betweenthe signal processor 1220 and the stimulator 1230, wherein the signalprocessor 1220 provides power and data to the stimulator 1230 andreceives data in return from the stimulator 1230. For example, thesignal processor 1220 can be configured to output signals power signals(e.g., via 1260) and data signals (e.g., via 1261) to the stimulator1230 (e.g., based on received inputs from a middle ear sensor or otherdevice). Such communication can be implemented via a similarcommunication protocol as implemented between the implantable batteryand/or communication module 1210 and the signal processor 1220. In someexamples, the power signals provided to the stimulator 1230 (e.g., via1260) are the same signals received by the signal processor 1220 fromthe implantable battery and/or communication module 1210 (e.g., via1250). Additionally, in some embodiments, the stimulator 1230 can beconfigured to provide feedback signals to the signal processor 1220(e.g., via 1261), for example, representative of an executed stimulationprocess.

FIG. 12B is an alternative schematic diagram illustrating exemplaryelectrical communication between an implantable battery and/orcommunication module 1210 b and a signal processor 1220 b in a cochlearimplant system similar to that shown in FIG. 12A. In the illustratedembodiment of FIG. 12B, the implantable battery and/or communicationmodule 1210 b includes a power signal generator 1211 and a separatesignal generator 1212. The power signal generator 1211 and signalgenerator 1212 are each configured to output a signal through a lead(e.g., 190) to the signal processor 1220 b. In some embodiments, thepower signal generator 1211 and the signal generator 1212 each generatesdigital signal for communication to the signal processor 1220 b. In somesuch embodiments, the digital signal (e.g., 1250) from the power signalgenerator 1211 can be communicated to the signal processor 1220 b at apower clock rate, while the digital signal (e.g., 1251 b) from thesignal generator 1212 can be communicated to the signal processor 1220 bat a data clock rate that is different from the power clock rate. Forinstance, in some configurations, power and data can be communicatedmost effectively and/or efficiently at different clock rates. In anexemplary embodiment, the power clock rate is approximately 30 kHz whilethe data clock rate is approximately 1 MHz. Utilizing different andseparately communicated power and data signals having different clockrates can increase the transfer efficiency of power and/or data from theimplantable battery and/or communication module 1210 b to the signalprocessor 1220 b.

In the illustrated embodiment, the implantable battery and/orcommunication module 1210 b includes a controller 1214 in communicationwith the power signal generator 1211 and the signal generator 1212. Insome examples, the controller 1214 is capable of adjusting communicationparameters such as the clock rate or content of the signal generator1212 and/or the power signal generator 1211. In an exemplary embodiment,the controller 1214 and/or the signal generator 1212 or power signalgenerator 1211 can communicate with, for example, a patient's externalprogrammer (e.g., as shown in FIG. 1). The controller 1214 and/or signalgenerator 1212 can be configured to communicate data to the signalprocessor 1220 b, such as updated firmware, signal processor 1220 btransfer functions, or the like. Additionally or alternatively, thecontroller 1214 can be configured to transmit signals such as audio orother signals streamed or otherwise received from one or more externaldevices as described elsewhere herein.

As shown, and similar to the example shown in FIG. 11B, the power signalgenerator 1211 outputs the generated signal to an amplifier 1290 and aninverting amplifier 1292. In some examples, both amplifiers are unitygain amplifiers. In some examples comprising digital signals, theinverting amplifier 1292 can comprise a digital NOT gate. The outputfrom the amplifier 1290 and the inverting amplifier 1292 are generallyopposite one another and are directed to the signal processor 1220 b. Inthe illustrated example, the receiving circuitry in the signal processor1220 b comprises a rectifier circuit 1222 that receives signals from theamplifier 1290 and the inverting amplifier 1292. Since the output of oneof the amplifiers 1290 and 1292 will be high, the rectifier circuit 1222can be configured to receive the opposite signals from the amplifiers1290 and 1292 and generate therefrom a substantially DC power output1223.

In various embodiments, the DC power 1223 can be used to power a varietyof components, such as the signal processor 1220 b itself, the middleear sensor, the electrical and/or acoustic stimulator 1230, or the like.The rectifier circuit 1222 can include any known appropriate circuitrycomponents for rectifying one or more input signals, such as a dioderectification circuit or a transistor circuit, for example. In someembodiments, signals from the power signal generator 1211 are generatedat a clock rate that is optimal for transmitting power through the lead(e.g., approximately 30 kHz). In the illustrated example of FIG. 12B,the rectifier circuit 1222 can be arranged in parallel with power linesthat are configured to communicate power signals to other componentswithin the system, such as the stimulator 1230, for example. Forinstance, in some embodiments, the same power signal (e.g., 1250)generated from the power signal generator 1211 and output via amplifiers1290 and 1292 can be similarly applied to the stimulator 1230. In somesuch examples, the stimulator 1230 includes a rectifier circuit 1222similar to the signal processor 1220 b for extracting DC power from thepower signal and the inverted power signal provided by amplifiers 1290and 1292, respectively. In alternative embodiments, the signal processor1220 b can similarly provide signals from a separate power signalgenerator 1211 to provide power signals (e.g., at approximately 30 kHz)to the stimulator 1230 similar to how power is provided from theimplantable battery and/or communication module 1210 b to the signalprocessor 1220 b in FIG. 12B.

In the example of FIG. 12B, the signal generator 1212 outputs a datasignal (e.g., 1251 b) to an amplifier 1294 and an inverting amplifier1296. In some examples, both amplifiers are unity gain amplifiers. Insome examples comprising digital signals, the inverting amplifier 1296can comprise a digital NOT gate. The output from the amplifier 1294 andthe inverting amplifier 1296 are generally opposite one another and aredirected to the signal processor 1220 b.

As described elsewhere herein, in some embodiments, the controller 1214and/or the signal generator 1212 is configured to encode data fortransmission via the output amplifiers 1294 and 1296. The signalprocessor 1220 b can include a signal extraction module 1224 configuredto extract the data from the signal(s) 1225 communicated to the signalprocessor 1220 b to produce a signal 1225 for use by the signalprocessor 1220 b. In some examples, the signal extraction module 1224 iscapable of decoding the signal that was encoded by the implantablebattery and/or communication module 1210 b. Additionally oralternatively, the signal extraction module 1224 can extract a resultingsignal 1225 resulting from the lead transfer function. In variousexamples, the extracted signal can include, for example, an updatedtransfer function for the signal processor 1220 b, a desired stimulationcommand, or other signals that affect operation of the signal processor1220 b.

In the example of FIG. 12B, the signal extraction module 1224 includes apair of tri-state buffers 1286 and 1288 in communication with signalsoutput from the signal generator 1212. The tri-state buffers 1286 and1288 are shown as having “enable” (ENB) signals provided by controller1226 in order to control operation of the tri-state buffers 1286 and1288 for extracting the signal from the signal generator 1212. Signalsfrom the signal generator 1212 and buffered by tri-state buffers 1286and 1288 are received by amplifier 1284, which can be configured toproduce a signal 1225 representative of the signal generated by thesignal generator 1212.

In some examples, communication of signals generated at the signalgenerator 1212 can be communicated to the signal processor 1220 b at aclock rate that is different from the clock rate of the signalsgenerated by the power signal generator 1211. For instance, in someembodiments, power signals from the power signal generator 1211 aretransmitted at approximately 30 kHz, which can be an efficient frequencyfor transmitting power. However, in some examples, the signals from thesignal generator 1212 are transmitted at a higher frequency than thesignal from the power signal generator 1211, for example, atapproximately 1 MHz. Such high frequency data transmission can be usefulfor faster data transfer than would be available at lower frequencies(e.g., the frequencies for transmitting the signal from the power signalgenerator 1211). Thus, in some embodiments, power and data can becommunicated from the implantable battery and/or communication module1210 b to the signal processor 1220 b via different communicationchannels at different frequencies.

Similar to the embodiment shown in FIG. 11B, in the illustrated exampleof FIG. 12B, the signal processor 1220 b includes a controller 1226 thatis in communication with the implantable battery and/or communicationmodule 1210 b. In some such embodiments, the controller 1226 in thesignal processor 1220 b is capable of monitoring the DC power 1223and/or the signal 1225 received from the implantable battery and/orcommunication module 1210 b. The controller 1126 can be configured toanalyze the received DC power 1223 and the signal 1225 and determinewhether or not the power and/or signal is sufficient. For example, thecontroller 1226 may determine that the signal processor 1220 b isreceiving insufficient DC power for stimulating a cochlear electrodeaccording to the signal processor 1220 b transfer function, or that datafrom the implantable battery and/or communication module 1210 b is notcommunicated at a desired rate. Thus, in some examples, the controller1226 of the signal processor 1220 b can communicate with the controller1214 of the implantable battery and/or communication module 1210 b andprovide feedback regarding the received communication. Based on thereceived feedback from the controller 1226 of the signal processor 1220b, the controller 1214 of the implantable battery and/or communicationmodule 1210 b can adjust various properties of the signals output by thepower signal generator 1211 and/or the signal generator 1212.

In the illustrated example of FIG. 12B, bidirectional communication 1251b between the implantable battery and/or communication module 1210 b andsignal processor 1220 b comprises signals from the amplifiers 1294 and1296 in one direction, and communication from controller 1226 tocontroller 1214 in the other direction. It will be appreciated that avariety of communication protocols and techniques can be used inestablishing bidirectional communication 1251 b between the implantablebattery and/or communication module 1210 b and signal processor 1220 b.

For example, in some embodiments, the implantable battery and/orcommunication module 1210 b need not include amplifiers 1294 and 1296,and instead transmits a signal and not its inverse to the signalprocessor 1220 b. In other examples, the signal processor includesamplifiers similar to 1294 and 1296, and outputs a signal and itsinverse back to the implantable battery and/or communication module 1210b. Additionally or alternatively, in some embodiments, the signalgenerator 1212 can be integral with the controller 1214 and/or thesignal extraction module 1224 can be integral with controller 1226,wherein controllers 1214 and 1226 can be in bidirectional communicationvia signal generator 1212 and/or the signal extraction module 1224. Ingeneral, the implantable battery and/or communication module 1210 b andthe signal processor 1220 b can be in bidirectional communication forcommunicating data signals separate from the power signals provided bypower signal generator 1211.

As described, separate communication channels for power (e.g., 1250) anddata (e.g., 1251 b) can be used for providing both power and data fromthe implantable battery and/or communication module 1210 b and thesignal processor 1220 b. This can allow for separate data and powerclocking rates in order to improve the power transmission efficiency aswell as the data transmission efficiency and/or rate. Moreover, in someexamples, if the bidirectional communication (e.g., 1251 b) between theimplantable battery and/or communication module 1210 b and the signalprocessor 1220 b fails (e.g., due to component failure, connectionfailure, etc.), data for communication from the implantable batteryand/or communication module 1210 b can be encoded in the power signalsfrom the power signal generator 1211 and transmitted to the signalprocessor 1220 b via 1250. Thus, similar to the embodiment describedwith respect to FIG. 11B, both power and data can be transmitted via thesame signal.

In some examples, the signal extraction module 1224 can be configured toreceive data received from the power signal generator 1211, for example,via an actuatable switch that can be actuated upon detected failure ofcommunication 1251 b. In other examples, the signal extraction module1224 and/or the controller 1226 can generally monitor data from thepower signal generator 1211 and identify when signals received from thepower signal generator 1211 include data signals encoded into thereceived power signal in order to determine when to consider the powersignals to include data.

Accordingly, in some embodiments, the configuration of FIG. 12B can beimplemented to establish efficient, bidirectional communication betweenthe implantable battery and/or communication module 1210 b and thesignal processor 1220 b. Failure in bidirectional communication 1251 bcan be identified manually and/or automatically. Upon detection offailure in the bidirectional communication 1251 b, the controller 1214can encode data into the power signal output from the power signalgenerator 1211, and power and data can be combined into a single signalsuch as described with respect to FIG. 11B.

FIG. 12C is another alternative schematic diagram illustrating exemplaryelectrical communication between an implantable battery and/orcommunication module 1210 c and a signal processor 1220 c in a cochlearimplant system similar to that shown in FIG. 12A. Similar to theembodiment of FIG. 12B, in the illustrated embodiment of FIG. 12C, theimplantable battery and/or communication module 1210 c includes a powersignal generator 1211 configured to output a signal through a lead(e.g., 190) to the signal processor 1220 c. In some embodiments, thepower signal generator 1211 generates a digital signal (e.g., 1250) forcommunication to the signal processor 1220 c, for example, at a powerclock rate. The power signal generator 1211 and corresponding amplifiers1290, 1292, as well as rectifier circuit 1222, can operate similar todescribed with respect to FIG. 12B in order to extract DC power 1223and, in some examples, output power signals to further systemcomponents, such as stimulator 1230.

In the illustrated embodiment, the implantable battery and/orcommunication module 1210 c includes a signal generator 1213, which canbe capable of providing data signals to the signal processor. In someembodiments, the signal generator 1213 generates a digital signal forcommunication to the signal processor 1220 c. In some such embodiments,the digital signal (e.g., 1251 c) from the signal generator 1213 can becommunicated to the signal processor 1220 b at a data clock rate that isdifferent from the power clock rate. For instance, as describedelsewhere herein, in some configurations, power and data can becommunicated most effectively and/or efficiently at different clockrates. In an exemplary embodiment, the power clock rate is approximately30 kHz while the data clock rate is approximately 1 MHz. Utilizingdifferent and separately communicated power and data signals havingdifferent clock rates can increase the transfer efficiency of powerand/or data from the implantable battery and/or communication module1210 c to the signal processor 1220 c.

The embodiment of FIG. 12C includes a controller 1215 in communicationwith the power signal generator 1211 and the signal generator 1213. Insome examples, the controller 1215 is capable of adjusting communicationparameters such as the clock rate or content of the signal generator1213 and/or the power signal generator 1211. In an exemplary embodiment,the controller 1215 and/or the signal generator 1213 or power signalgenerator 1211 can communicate with, for example, a patient's externalprogrammer (e.g., as shown in FIG. 1). The controller 1215 and/or signalgenerator 1213 can be configured to communicate data to the signalprocessor 1220 c, such as updated firmware, signal processor 1220 ctransfer functions, or the like.

Similar to the example in FIG. 12B, in the example of FIG. 12C, thesignal generator 1213 outputs a data signal (e.g., 1251) to an amplifier1295 and an inverting amplifier 1297. In some examples, both amplifiersare unity gain amplifiers. In some examples comprising digital signals,the inverting amplifier 1297 can comprise a digital NOT gate. The outputfrom the amplifier 1295 and the inverting amplifier 1297 are generallyopposite one another and are directed to the signal processor 1220 c.

As described elsewhere herein, in some embodiments, the controller 1215and/or the signal generator 1213 is configured to encode data fortransmission via the output amplifiers 1295 and 1297. The signalprocessor 1220 c can include a signal extraction module 1234 configuredto extract the data from the signal(s) communicated to the signalprocessor 1220 c to produce a signal for use by the signal processor1220 c. In some examples, the signal extraction module 1234 is capableof decoding the signal that was encoded by the implantable batteryand/or communication module 1210 c. Additionally or alternatively, thesignal extraction module 1234 can extract a signal resulting from thelead transfer function. In various examples, the extracted signal caninclude, for example, an updated transfer function for the signalprocessor 1220 c, a desired stimulation command, or other signals thataffect operation of the signal processor 1220 c.

In the example of FIG. 12C, similar to signal extraction module 1224 inFIG. 12B, the signal extraction module 1234 includes a pair of tri-statebuffers 1287 and 1289 in communication with signals output from thesignal generator 1213. The tri-state buffers 1287 and 1289 are shown ashaving “enable” (ENB) signals provided by controller 1227 in order tocontrol operation of the tri-state buffers 1287 and 1289 for extractingthe signal from the signal generator 1213. Signals from the signalgenerator 1213 and buffered by tri-state buffers 1287 and 1289 arereceived by amplifier 1285, which can be configured to produce a signalrepresentative of the signal generated by the signal generator 1213.

As described elsewhere herein, in some examples, communication ofsignals generated at the signal generator 1213 can be communicated tothe signal processor 1220 c at a clock rate that is different from theclock rate of the signals generated by the power signal generator 1211.For instance, in some embodiments, power signals from the power signalgenerator 1211 are transmitted at approximately 30 kHz, which can be anefficient frequency for transmitting power. However, in some examples,the signals from the signal generator 1213 are transmitted at a higherfrequency than the signal from the power signal generator 1211, forexample, at approximately 1 MHz. Such high frequency data transmissioncan be useful for faster data transfer than would be available at lowerfrequencies (e.g., the frequencies for transmitting the signal from thepower signal generator 1211). Thus, in some embodiments, power and datacan be communicated from the implantable battery and/or communicationmodule 1210 c to the signal processor 1220 c via different communicationchannels at different frequencies.

In the illustrated example of FIG. 12C, the signal processor 1220 cincludes a signal generator 1217 and controller 1227 that is incommunication with the signal generator 1217. Similar to the operationof signal generator 1213 and amplifiers 1295 and 1299, the signalgenerator can be configured to produce output signals to amplifiers 1287and 1289, which can be configured to output signals to the implantablebattery and/or communication module 1210 c.

In some embodiments, the controller 1227 in the signal processor 1220 cis capable of monitoring the DC power 1223 and/or the signal receivedfrom the implantable battery and/or communication module 1210 c. Thecontroller 1126 can be configured to analyze the received DC power 1223and the signal and determine whether or not the power and/or signal issufficient. For example, the controller 1227 may determine that thesignal processor 1220 c is receiving insufficient DC power forstimulating a cochlear electrode according to the signal processor 1220c transfer function, or that data from the implantable battery and/orcommunication module 1210 c is not communicated at a desired rate. Thus,in some examples, the controller 1227 of the signal processor 1220 ccause the signal generator 1217 to generate communication signals tosend to implantable battery and/or communication module 1210 c. Suchsignals can be used to provide feedback regarding signals received bythe signal processor 1220 c, such as the DC power 1223.

In the example of FIG. 12C, amplifiers 1295 and 1297 are shown asincluding tri-state amplifiers (e.g., tri-state buffers) controllable bythe controller 1227. Similar to the configuration in the signalprocessor 1220 c, the implantable battery and/or communication module1210 c includes a signal extraction module 1235 configured to extractdata from the signal(s) communicated to the implantable battery and/orcommunication module 1210 c from signal generator 1217 of the signalprocessor 1220 c. The signal extraction module 1235 includes tri-stateamplifiers 1295 and 1297 in communication with signals output from thesignal generator 1217. Signals from the signal generator 1217 andreceived at tri-state buffers 1295 and 1297 are received by amplifier1299, which can be configured to produce a signal representative of thesignal generated by the signal generator 1217 to controller 1215 of theimplantable battery and/or communication module 1210. Thus, in someembodiments, the controller 1227 of the signal processor 1220 c isconfigured to communicate data back to the implantable battery and/orcommunication module 1210 a via amplifiers 1287 and 1289.

As described with respect to other embodiments, based on the receivedfeedback from the controller 1227 of the signal processor 1220 c, thecontroller 1215 of the implantable battery and/or communication module1210 c can adjust various properties of the signals output by the powersignal generator 1211 and/or the signal generator 1213.

Thus, in the illustrated example of FIG. 12C, bidirectionalcommunication 1251 between the implantable battery and/or communicationmodule 1210 c and signal processor 1220 c includes communication betweendifferent signal extraction modules 1235 and 1234. As shown, both theimplantable battery and/or communication module 1210 c and the signalprocessor 1220 c include a controller (1215, 1227) that communicateswith a signal generator (1213, 1217) for producing output signals. Thesignal generator (1213, 1217) outputs signals via tri-state amplifiers,including one inverting amplifier (1297, 1289) for communication acrossbidirectional communication 1251 c for receipt by the other signalextraction module (1234, 1235).

Thus, in some embodiments, bidirectional communication 1251 c betweenthe implantable battery and/or communication module 1210 c and thesignal processor 1220 c can be enabled by each of the implantablebattery and/or communication module and the signal processor receivingand transmitting data via approximately the same communication structureas the other. In some such examples, the implantable battery and/orcommunication module 1210 c and the signal processor 1220 c include dataextraction modules 1235 and 1234, respectively, configured both tooutput signals from a signal generator (e.g., via 1213 or 1217) andreceive and extract signals (e.g., via 1299 and 1285).

In the example of FIG. 12C, of tri-state amplifiers 1295 and 1297 thatselectively (e.g., via “enable” control from controller 1215) output thesignal from signal generator 1213, amplifier 1297 is shown as aninverting amplifier. Similarly, of tri-state amplifiers 1287 and 1289that selectively (e.g., via “enable” control from controller 1227)output the signal from signal generator 1217, amplifier 1289 is shown asan inverting amplifier. As described elsewhere herein, communicating asignal and its inverse (e.g., via 1295 and 1297) allows communicationwith no net charge flow between the implantable battery and/orcommunication module 1210 c and the signal processor 1220 c. Thus,bidirectional communication between the implantable battery and/orcommunication module 1210 c and the signal processor 1220 c can beperformed without a net charge flow between the components.

As described elsewhere herein, power from power generator 1211 and datafrom signal generator 1213 (and/or signal generator 1217) can becommunicated at different clocking rates to optimize power and datatransfer. In some examples, if data communication (e.g., viabidirectional communication 1251 c) fails, the controller 1215 can beconfigured to control power generator 1211 to provide both power anddata signals via amplifiers 1290 and 1292, for example, as describedwith respect to FIG. 11B.

Accordingly, in some embodiments, the configuration of FIG. 12C can beimplemented to establish efficient, bidirectional communication betweenthe implantable battery and/or communication module 1210 and the signalprocessor 1220. Failure in bidirectional communication 1251 can beidentified manually and/or automatically. Upon detection of failure inthe bidirectional communication 1251, the controller 1215 can encodedata into the power signal output from the power signal generator 1211,and power and data can be combined into a single signal such asdescribed with respect to FIG. 11B.

As discussed elsewhere herein, different safety standards can existregarding electrical communication within the patient's body. Forexample, safety standards can limit the amount of current that cansafely flow through a patient's body (particularly DC current). As shownin FIGS. 11B, 12B, and 12C, each of the illustrated communication pathsbetween the implantable battery and/or communication module and thesignal processor are coupled to output capacitors. The capacitorspositioned at the inputs and outputs of the implantable battery and/orcommunication module and the signal processor can substantially block DCcurrent from flowing therebetween while permitting communication of ACsignals.

As described elsewhere herein, in some embodiments, the datacommunicated between the implantable battery and/or communication moduleand the signal processor (e.g., from the signal generator) is encoded.In some such examples, the encoding can be performed according to aparticular data encoding method, such as an 8b/10b encoding scheme, toachieve DC balance in the communicated signal. For example, in someembodiments, data is encoded such that the numbers of high and low bitscommunicated between components at each clock signal meet certaincriteria to prevent a charge of a single polarity from building up onany of the capacitors. Such encoding can minimize the total charge thatflows between the implantable battery and/or communication module andthe signal processor during communication.

While described and illustrated as representing communication betweenthe implantable battery and/or communication module and the signalprocessor, it will be appreciated that communication configurations suchas shown in FIGS. 10, 11A, 11B, 12A, 12B, and 12C can be implementedbetween any pair of devices generally in communication with one another.For example, isolating circuitry (e.g., R_(Can)) can be included in anyof the system components (e.g., middle ear sensor, acoustic stimulator,electrical stimulator, etc.) to effectively isolate the ground signalsfrom each component from its respective can. Similarly, the exemplarycapacitive AC coupling with DC blocking capacitors and DC balancingencoding as described elsewhere herein can be incorporated as thecommunication interface between any two communicating components.

As described, data can be communicated from the implantable batteryand/or communication module to the signal processor for a variety ofreasons. In some examples, data is that communicated to the implantablebattery and/or communication module from an external component, such asa programmer as shown in FIG. 1. In an exemplary process, a programmer,such as a clinician's computer, can be used to communicate with apatient's fully implanted system via a communication configuration suchas shown in FIG. 11B, 12B, or 12C. For example, a programmer cancommunicate wirelessly (e.g., via Bluetooth or other appropriatecommunication technique) with the patient's implantable battery and/orcommunication module. Signals from the programmer can be sent from theimplantable battery and/or communication module to the signal processorvia the communication configurations of FIG. 11B, 12B, or 12C.

During such processes, a clinician can communicate with the signalprocessor, and, in some cases, with other components via the signalprocessor. For example, the clinician can cause the signal processor toactuate an electrical and/or an acoustic stimulator in various ways,such as using various electrical stimulation parameters, combinations ofactive contact electrodes, various acoustic stimulation parameters, andvarious combinations thereof. Varying the stimulation parameters in realtime can allow the clinician and patient to determine effectiveness ofdifferent stimulation techniques for the individual patient. Similarly,the clinician can communicate with the signal processor to updatetransfer function. For example, the clinician can repeatedly update thetransfer function signal processor while testing the efficacy of eachone on the individual patient. In some examples, combinations ofstimulation parameters and signal processor transfer functions can betested for customized system behavior for the individual patient.

Additional Input Signals/Sources

As described elsewhere herein, while many examples show a middle earsensor being in communication with an implanted signal processor, invarious embodiments, one or more additional or alternative input sourcescan be included. For instance, in some embodiments, a microphone can beimplanted under a user's skin and can be placed in communication withthe signal processor (e.g., via a detachable connector such as 171). Thesignal processor can receive input signals from the implanted microphoneand provide signals to the stimulator based on the received input signaland the signal processor transfer function.

Additionally or alternatively, one or more system components can beconfigured to receive broadcast signals for converting into stimulationsignals. FIG. 13 is a schematic system diagram showing an implantablesystem configured to receive broadcast signals from a broadcast device.As shown in the example of FIG. 13, a broadcast source 1350 broadcasts asignal via communication link 1360. The communication link 1360 caninclude communication via a variety of communication protocols, such asWi-Fi, Bluetooth, or other known data transmission protocols. Broadcastsource 1350 can include any of a variety of components, such as a mediasource (e.g., television, radio, etc.), communication device (e.g.,telephone, smartphone, etc.), a telecoil or other broadcast system(e.g., at a live performance), or any other source of audio signals thatcan be transmitted to an implanted system or to an external component ofan implanted system (e.g., a system programmer, etc.).

An implantable system including a programmer 1300, an implantablebattery and/or communication module 1310, a signal processor 1320, and astimulator 1330 can generally receive the data from the broadcast source1350 via communication link 1360. In various embodiments, any number ofcomponents in the implantable system can include a receiving device,such as a telecoil, configured to receive broadcast signals for eventualconversion into stimulation signals.

For instance, in some embodiments, programmer 1300 can include atelecoil relay configured to receive broadcast telecoil signals from abroadcast source 1350. The programmer can be configured to subsequentlycommunicate a signal representative of the received broadcast signal tothe implantable battery and/or communication module 1310 and/or thesignal processor 1320, e.g., via a Bluetooth communication. If thecommunication is received from the programmer 1300 via the implantablebattery and/or communication module 1310, the implantable battery and/orcommunication module 1310 can communicate the signal to the signalprocessor, for example, as described in any of FIG. 11A, 11B, 12A, or12C.

In some such embodiments, the signal processor 1320 can be configured toreceive such signals from the implantable battery and/or communicationmodule 1310 and output stimulation signals to the stimulator 1330 basedon the received signals and the signal processor transfer function. Inother examples, the signal processor 1320 can include a telecoil relayor other device capable of receiving broadcast signals from thebroadcast source 1350. In some such embodiments, the signal processor1320 processes the received signals according to the signal processortransfer function and outputs stimulations signals to the stimulator1330.

In some embodiments, the signal processor 1320 can be in communicationwith a plurality of input sources, such as, for example, a combinationof an implanted microphone, a middle ear sensor, and a broadcast source1350 (e.g., via the implantable battery and/or communication module1310). In some such examples, the signal processor can be programmedwith a plurality of transfer functions, each according to respectiveinput sources. In such embodiments, the signal processor can identifywhich one or more input sources are providing input signals and processeach such input signal according to the transfer function associatedwith its corresponding input source.

In some examples, a signal processor 1320 receiving a plurality of inputsignals from a corresponding plurality of input sources effectivelycombines the signals when producing a stimulation signal to thestimulator 1330. That is, in some embodiments, input sources arecombined to form the stimulation signal from the signal processor 1320.In some such examples, a user may be able to mix the various receivedinput signals in any way desired. For example, a user may choose toblend a variety of different input streams, such as an input from amiddle ear sensor or other implanted device, a signal received from anexternal device (e.g., a telecoil relay, a Bluetooth connection such asto a smartphone, etc.), and the like. In an exemplary configuration, auser may elect to equally blend two input sources such that thestimulation signal is based 50% on a first input source and 50% on asecond input source.

Additionally or alternatively, a user may elect to effectively “mute”one or more input sources so that the signal processor 1320 outputsstimulations signals based on input signals received from unmutedsources. Similarly, a user may be able to select a single source fromwhich to process received input signals. For example, in someembodiments, a user may select to have signals received from broadcastsource 1350 processed and converted into stimulation signals whilehaving signals received from, for example, a middle ear sensor,disregarded.

In some examples, direct communication with the signal processor can beused to test the efficacy of a given signal processor transfer functionand associated stimulation (e.g., acoustic or electrical) parameters.For example, the programmer can be used to disable input signals from amiddle ear sensor or other input source and provide a customized signalto the signal processor to simulate a signal from the input source. Thesignal processor processes the received signal according to its transferfunction, and actuates the electrical stimulator and/or the acousticstimulator accordingly. The processor can be used to test a variety ofcustomized “sounds” to determine the efficacy of the signal processortransfer function for the given patient for each “sound.”

FIG. 14 is a process flow diagram illustrating an exemplary process forestablishing a preferred transfer function for a patient. The method caninclude connecting an external programmer to the implantable batteryand/or communication module (1450). Connecting can include, for example,establishing a wireless connection (e.g., Bluetooth communication)between an external programmer and the implantable battery and/orcommunication module. The external programmer can include any variety ofcomponents capable of providing programming instructions to theimplantable battery and/or communication module, such as a computer,smartphone, tablet, or the like.

Once communication is established, if there is no signal processortransfer function active (1452), a signal processor transfer functioncan be established (1454). If a transfer function is already active, orafter one has been established (1454), the programmer can be used toinput one or more simulated “sounds” to the signal processor. Such“sounds” can be received and treated by the signal processor as if theywere received from an input source such as a middle ear sensor. The“sounds” can be, for example, computer-generated signals designed tosimulate various input signals, such as a range of frequencies, phoneticsounds, or other distinguishable sound characteristics.

The process can further include testing the efficacy of the signalprocessor transfer function (1458). This can include, for example,determining how well the patient responds to each sound provided a givensignal processor transfer function. In some examples, this can includerating the transfer function under test for each of the “sounds” anddetermining an aggregate score for the transfer function based on thescore(s) associated with the one or more “sounds.”

After testing the efficacy of the signal processor transfer function, ifnot all desired transfer functions have been tested (1460), the signaltransfer function can be updated (1454). The one or more simulated“sounds” can be input to the signal processor (1456) and processedaccording to the updated transfer function, and the efficacy of theupdated transfer function can be tested (1458). Once all desiredtransfer functions have been tested (1460), a signal processor transferfunction for the user can be created or selected and implemented for thepatient (1462). In some examples, a best transfer function of the testedtransfer functions is selected based on a user preference, a highestscore, or other metric. In other examples, composite results from thetested transfer functions can be combined to create a customizedtransfer function for the patient.

In other examples, rather than continually updating the signal processortransfer function, simulated “sounds” can be pre-processed outside ofthe signal processor, for example, on site with a clinician oraudiologist. For instance, in an exemplary process, one or moresimulated sounds can be pre-processed using processing software toestablish simulated stimulation signals that would result from aparticular input signal being processed via a particular transferfunction. In some examples, such signals can be transferred to, forexample, the signal processor for directly applying stimulation signalsto the wearer.

Communication to the stimulator can be performed, for example, directlyfrom various system components, such as a programmer. In other examples,such communication can be performed via the implantable battery and/orcommunication module and signal processor. For instance, in an exemplaryembodiment, pre-processed signals can be communicated to the implantablebattery and/or communication module via a wireless (e.g., Bluetooth)communication. The implantable battery and/or communication module cancommunicate the pre-processed signals to the signal processor, which canbe configured with a unity transfer function. Thus, the signal processormerely passes the pre-processed signals on to the stimulator forperforming stimulation.

FIG. 15 is a process flow diagram showing an exemplary method of testingthe efficacy of one or more sounds using one or more transfer functionsvia pre-processed signals. In the method of FIG. 15, a sound can beloaded (1550), for example, into an application or processing softwarecapable of processing the received sound. In some examples, the soundcan be a simulated sound, such as a computer-generated signalrepresenting a desired sound. In other examples, the sound can include arecording of an actual sound, such as a person's voice or otherstimulus. The loaded sound can be pre-processed according to a transferfunction to generate a stimulation signal (1552). The pre-processing canbe performed, for example, on a stand-alone work station, a systemprogrammer, or the like.

The method of FIG. 15 further comprises the step of applying thestimulation signal from the pre-processed sound to the stimulator of theimplanted system (1554). As described elsewhere herein, suchcommunication of the stimulation signal to the stimulator can beperformed in a variety of ways, such as directly to the stimulator(e.g., from an external workstation, the user's programmer, etc.) orthrough the signal processor.

Upon applying the stimulation signal (1554), the method can furtherinclude the step of testing the efficacy of the stimulation signal(1556). This can include, for example, testing a user's comprehension ofthe initial sound from the received stimulation signal, receiving arating score from the user, or any other appropriate way of resting theefficacy of the stimulation signal. Since the stimulation signal appliedin step 1554 is based on the sound and the transfer function used forpre-processing, testing the efficacy of the stimulation signal issimilar to testing the efficacy of the transfer function for the givensound.

After testing the efficacy of the stimulation signal, it can bedetermined whether all simulation transfer functions have been testedfor the given sound (1558). If not, the method can include the step ofestablishing or updating a simulated transfer function (1560), andrepeating the steps of pre-processing the sound to establish astimulation signal (1552), applying the stimulation signal (1554), andtesting the efficacy of the stimulation signal (1556) all according tothe updated transfer function. Thus, a given sound can be processedaccording to a plurality of transfer functions, and a plurality ofcorresponding stimulation signals can be tested with respect to a givenuser.

In some examples, the process of FIG. 15 can be performed in real time.For instance, in some embodiments, a device in communication with thestimulator in an implanted system (e.g., directly via wirelesscommunication with the stimulator or indirectly via signal processor)can cycle through various simulated transfer functions whilepre-processing sound signals prior to communicating them to the user'ssystem. In some such examples, after establishing a preferred processingtechnique (e.g., simulated transfer function) for a given sound (e.g.,in step 1562), the user's signal processor transfer function can beupdated to reflect the preferred transfer function for the given sound.

Additionally or alternatively, the process of FIG. 15 can be repeatedfor a plurality of different sounds. In some embodiments, a plurality ofsounds can be pre-processed according to a plurality of differentsimulated transfer functions, and the resulting generated stimulationsignals can be stored in a database. A testing device, such as aworkstation, programmer, etc., can be used to carry out the method ofFIG. 15 while using the database of stimulations signals to test theefficacy of various transfer functions with respect to various soundsfor a user.

In some examples, such a database can be used to fit a user with aparticular implant system. For example, stimulation signals generated bypre-processing a plurality of sounds can be communicated to theimplanted stimulator of a user having an implanted stimulator andcochlear electrode in order to test the efficacy of the transferfunction simulated in the pre-processing. In various examples, aplurality generated stimulation signals associated with a given soundcan be applied to the stimulator until a preferred simulated transferfunction is established. In other examples, generated stimulationsignals representative of a plurality of sounds can be established foreach of a plurality of transfer functions, such that each transferfunction can be tested on a user for a plurality of sounds prior totesting another transfer function.

FIG. 16 is a schematic representation of an exemplary database ofpre-processed sound signals. As shown, the database is represented as atable having n rows corresponding to different sounds (sound 1, sound 2,. . . , sound n) and m columns corresponding to different simulatedtransfer functions (simulated transfer function 1, simulated transferfunction 2, . . . , simulated transfer function m). As shown, at theintersection of each row (i) and each column (j), pre-processing a soundi with a simulated transfer function j results in stimulation signal(i,j). In some embodiments, a table such of stimulation signalsgenerated from pre-processed sounds such as shown in FIG. 16 can bestored in a database of pre-processed sound signals for device fittingfor a user.

As described elsewhere herein, in various fitting processes, a sound maybe selected from database (e.g., sound 1), and a plurality of differentstimulation signals (e.g., stimulation signal (1,1), stimulation signal(1,2), . . . , stimulation signal (1,m)) can be communicated to animplanted stimulator. Such stimulation signals generally correspond tothe result of the sound (e.g., sound 1) being pre-processed according tovarious simulated transfer functions (1-m). As described with respect toFIG. 15, a preferred stimulation signal (and thus, a preferredcorresponding simulated transfer function) can be established for thegiven sound (e.g., sound 1). A similar process can be repeated for eachsound in the database. In various examples, one or more signal processortransfer functions can be communicated to the signal processor based onthe determined preferred simulated transfer function(s). For instance,in some example, the simulated transfer function that was preferredamong the most sounds may be implemented as the signal processortransfer function. In other embodiments, the signal processor include aplurality of transfer functions, and can apply different transferfunctions to different detected sounds depending on the preferredtransfer function for each sound.

In other exemplary fitting processes, a plurality of stimulation signals(e.g., stimulation signal (1,1), stimulation signal (2,1), . . . ,stimulation signal (n,1)) corresponding to a single simulated transferfunction (e.g., simulated transfer function 1) can be applied to astimulator. Such stimulation signals correspond to a plurality of soundsthat are pre-processed according to the single simulated transferfunction. This can be used to test the efficacy of the selected transferfunction. The process can be repeated for a plurality of simulatedtransfer functions (e.g., 2-m) in order to determine a best transferfunction across a variety of sounds (e.g., sounds 1-n).

In general, a database of stimulation signals generated bypre-processing sound signals via various transfer functions such asshown in FIG. 16 can be useful for expediting the testing of suchtransfer functions for a particular user. Pre-processing such soundsallows for the processing to be done, for example, in a lab or on aworkstation prior to any fitting process, and allows for efficientapplication of stimulation signals corresponding to different transferfunctions to a user's stimulator without requiring updates of the signalprocessor. Additionally, such pre-processing can allow for more advancedor computationally demanding processing techniques to be tested forefficacy even if such processing techniques may not yet be effectivelyimplemented by an implanted signal processor (e.g., due to varioushardware limitations). Testing the efficacy of such processingtechniques can motivate evolution of processing methodologies andhardware capability, for example, in an effort to employ more complexprocessing techniques in the future.

Various features and functions of implantable systems have beendescribed herein. As described, in various embodiments, systemoperation(s) can be adjusted based on communication with the implantedsystem from components located outside of the body while the systemremains implanted. In some embodiments, the system may include anynumber of external components capable of interfacing with the system ina variety of ways.

FIG. 17 is a schematic diagram illustrating possible communicationbetween a variety of system components according to some embodiments ofa fully-implantable system. In the illustrated embodiment, implantedcomponents (outlined in broken line) of a system include an implantablebattery and/or communication module 1710, a signal processor 1720, and astimulator 1730. Such implanted components can operate according tovarious examples as described herein in order to effectively stimulate auser (e.g., via electrical and/or acoustic stimulation) in response toreceived input signals.

The schematic illustration of FIG. 17 includes a plurality of externaldevices capable of wirelessly interfacing with one or more of theimplanted components, for example, via communication link 1725. Suchdevices can include a programmer 1700, a charger 1702, asmartphone/tablet 1704, a smartwatch or other wearable technology 1706,and a fob 1708. In some examples, such components can communicate withone or more implantable components via one or more communicationprotocols via wireless communication link 1725, such as Bluetooth,Zigbee, or other appropriate protocols. In various embodiments,different external devices are capable of performing one or morefunctions associated with system operation. In some such embodiments,each external device is capable of performing the same functions as theothers. In other examples, some external devices are capable ofperforming more functions than others.

For example, a programmer 1700 can be capable of interfacing wirelesslywith one or more implantable components in order to control a variety ofoperating parameters of the implanted system. For example, in someembodiments, programmer 1700 can be configured to adjust a signalprocessor transfer function or select an operating profile (e.g.,associated with a particular signal processor transfer functionaccording to a particular user, environment, etc.). In some examples,the programmer 1700 can be used to establish user profiles, such aspreferred signal processor transfer functions, as described elsewhereherein. The programmer 1700 can additionally or alternatively be used toturn the system on or off, adjust the volume of the system, receive andstream input data to the system (e.g., the implantable battery and/orcommunication module 1710). In some embodiments, the programmer 1700includes a display for displaying various information to the user. Forexample, the display can be used to indicate a mode of operation (e.g.,a loaded user profile), a remaining power level, or the like. In somesuch embodiments, the display can function as a user interface by whicha user can adjust one or more parameters, such as volume, profile, inputsource, input mix, and the like.

In some embodiments, a charger 1702 can be used to charge one or moreinternal batteries or other power supplies within the system, such as inthe implantable battery and/or communication module 1710. In someexamples, the charger 1702 can include the same functionality as theprogrammer 1700, including, for instance, a display and/or userinterface. In some such embodiments, the programmer 1700 and the charger1702 can be integrated into a single device.

In some embodiments, various external devices such as a smartphone ortablet 1704 can include an application (“app”) that can be used tointerface with the implanted system. For example, in some embodiments, auser may communicate (e.g., via link 1725) with the system via thesmartphone or tablet 1704 in order to adjust certain operating factorsof the system using a predefined app to provide an interface (e.g., avisual interface via a display integrated into the external device). Theapp can assist the user in adjusting various parameters, such as volume,operating profile, on/off, or the like. In some examples, thesmartphone/tablet 1704 can be used to stream input signals to theimplanted system, such as media or communication playing on thesmartphone/tablet 1704.

In some systems, a smartwatch or other wearable technology 1706 caninteract with the system in a similar way as the smartphone/tablet 1704.For example, the smartwatch or other wearable technology 1706 caninclude an app similar to that operable on the smartphone/tablet tocontrol operation of various aspects of the implanted system, such asvolume control, on/off control, etc.

In some embodiments, the fob 1708 can be used to perform basic functionwith respect to the implanted system. For instance, in some embodiments,a fob 1708 can be used to load/implement a particular operating profileassociated with the fob 1708. Additionally or alternatively, the fob1708 can function similar to the shut-off control 104 of FIG. 1, and canbe used to quickly disable and/or mute the system. As describedelsewhere herein, in some examples, the same device used to disableand/or mute the system (e.g., fob 1708) can be used to enable and/orunmute the system.

The schematic diagram of FIG. 17 further includes a broadcast source1750 configured to broadcast signals 1760 that are receivable via one ormore external devices and/or one or more implanted system components.Similar to the broadcast source 1350 in FIG. 13, broadcast source 1750can be configured to emit signals that can be turned into stimulationsignals for application by stimulator 1730. Broadcast signals 1760 caninclude, for example, telecoil signals, Bluetooth signals, or the like.In various embodiments, one or more external devices, such as aprogrammer 1700, charger 1702, smartphone/tablet 1704,smartwatch/wearable device 1706, and/or fob 1708 can include a component(e.g., a telecoil relay) capable of receiving broadcast signal 1760. Theexternal device(s) can be further configured to communicate a signal toone or more implanted components representative of the receivedbroadcast signal 1760 for applying stimulation to the patient based onthe broadcast signal 1760.

Additionally or alternatively, in some embodiments, one or moreimplanted system components, such as an implantable battery and/orcommunication module 1710, a signal processor 1720, and/or a stimulator1730 can be configured to receive broadcast signals 1750. Suchcomponent(s) can be used to generate stimulation signals for applying toa user via stimulator 1730 according to the received broadcast signals1750.

As described, in various embodiments, different external devices caninterface with implanted components to adjust operation of the system invarious ways. In some embodiments, not all components are capable ofperforming the same functions as other components. FIG. 18 is a chartshowing the various parameters that are adjustable by each of a varietyof external devices according to some exemplary systems. In the exampleof FIG. 18, entries in the chart including an ‘X’ represent a componentconfigured to perform a corresponding function. Other examples arepossible in which different components include different functionalitythan is represented by the example of FIG. 18.

Generally, the modularity of such systems allows system modifications,such as repairing, replacing, upgrading, etc., of system componentsand/or transitioning from a partially- to fully-implantable system, tobe performed with minimal disturbance of implanted system components.For example, an implanted cochlear electrode and electrical stimulatorand/or acoustic stimulator can remain in place while other systemcomponents are implanted and/or replaced, reducing the risk ofadditional procedures damaging the patient's cochlear tissue.Additionally, the communication techniques as described herein can beused to help customize and/or optimize a signal processor transferfunction for a particular patient, as well as enable the system to meetsafety standards, provide adequate power and data transfer rates betweensystem components, and operate at a high efficiency. It will beappreciated that, while generally described herein with respect toimplantable hearing systems, communication techniques described can beused in a variety of other implantable systems, such as variousneuromodulation devices/systems, including, for example, painmanagement, spinal cord stimulation, brain stimulation (e.g., deep brainstimulation), and the like.

Various non-limiting embodiments have been described. These and othersare within the scope of the following claims.

The invention claimed is:
 1. A cochlear implant system comprising: astimulator configured to provide stimulation signals; an input sourceconfigured to receive an input representative of ambient sound andgenerate an input signal representative of the received input; a signalprocessor in communication with the stimulator and the input source, thesignal processor being programmed with a transfer function such that thesignal processor outputs a stimulation signal to the stimulator based onthe input signal received from the input source and the transferfunction; an implantable battery and/or communication module including:a signal generator configured to generate electrical signals forcommunication to the signal processor; and an inverting amplifier incommunication with the signal generator and configured to outputinverted electrical signals; and a first lead coupling the signalprocessor and the implantable battery and/or communication module;wherein the implantable battery and/or communication module isconfigured to provide the electrical signals from the signal generatorand the inverted electrical signals from the inverting amplifier to thesignal processor via the first lead.
 2. The implant system of claim 1,wherein the first lead is detachable from the signal processor.
 3. Theimplant system of claim 1, wherein: the signal processor includescircuitry configured to receive the electrical signals and the invertedelectrical signals from the implantable battery and/or communicationmodule, a can housing the circuitry, and a first impedance between thecircuitry and the can to reduce unintended electrical communication ofthe stimulation signals to the circuitry of the signal processor; andthe implantable battery and/or communication module includes circuitryincluding the signal generator and the inverting amplifier, a cansurrounding and housing the circuitry, and a second impedance betweenthe circuitry and the can to reduce unintended electrical communicationof the stimulation signals to the circuitry of the implantable batteryand/or communication module.
 4. The implant system of claim 3, whereinthe first impedance comprises an open circuit and/or the secondimpedance comprises an open circuit.
 5. The implant system of claim 1,wherein the signal processor includes a rectifier circuit incommunication with the first lead, wherein the rectifier circuit isconfigured to receive both the electrical signals and the invertedelectrical signals from the implantable battery and/or communicationmodule and output a substantially DC electrical output signal.
 6. Theimplant system of claim 5, wherein the signal generator comprises apower signal generator; that the electrical signals comprise powersignals and the inverted electrical signals comprise inverted powersignals, the power signals and the inverted power signals comprisingdigital signals having a first clocking rate; and the implantablebattery and/or communication module is further configured to output datasignals to the signal processor at a second clocking rate, the secondclocking rate being higher than the first.
 7. The implant system ofclaim 1, wherein the first lead is coupled to the signal processor andthe implantable battery and/or communication module by one or morecapacitors such that electrical communication between the signalprocessor and the implantable battery and/or communication module viathe first lead is substantially an AC signal.
 8. The implant system ofclaim 1, further comprising a third lead coupling the signal processorand the stimulator, the third lead being detachable from the signalprocessor and/or the stimulator.
 9. The implant system of claim 1,further comprising an external programmer in wireless communication withthe implantable battery and/or communication module, the externalprogrammer being configured to adjust operation of the signal processorvia communication with the implantable battery and/or communicationmodule.
 10. The implant system of claim 9, wherein the externalprogrammer is configured to: disable input signals from the input sourceto the signal processor; and provide one or more custom input signals tothe signal processor; such that the signal processor processes the oneor more custom input signals according to the transfer function andoutputs the stimulation signal to the stimulator based on the receivedcustom input signals.
 11. The implant system of claim 10, wherein theexternal programmer is further configured to, for a plurality oftransfer functions, change the transfer function and provide the one ormore custom input signals to the signal processor to test an efficacy ofthe plurality of transfer functions.
 12. A method of providing acommunication signal and electrical power from an implanted batteryand/or communication module of a cochlear implant system to an implantedsignal processor comprising: generating a first signal via a signalgenerator within the implanted battery and/or communication module;inverting the generated first signal via an inverter to produce aninverted first signal; outputting the generated first signal and theinverted first signal to a lead via one or more capacitive connections;receiving, via the one or more capacitive connections, the generatedfirst signal and the inverted first signal at the implanted signalprocessor; rectifying one or both of the received generated first signaland the received inverted first signal to generate a substantially DCoutput signal; and extracting data from the received first signal. 13.The method of claim 12, wherein the extracted data from the receivedfirst signal is representative of the first signal generated via thesignal generator.
 14. The method of claim 12, further comprisinganalyzing the substantially DC output signal, and if the substantiallyDC output signal is insufficient to provide a stimulation signal,increasing the electrical power provided to the signal generator. 15.The method of claim 12, wherein the first signal is substantially an ACsignal.
 16. The method of claim 12, wherein the cochlear implant systemfurther includes an implanted cochlear electrode, the method furthercomprising providing a first impedance between the cochlear electrodeand the implanted signal processor and providing a second impedancebetween the cochlear electrode and the implanted battery and/orcommunication module.
 17. The method of claim 16, wherein the firstimpedance comprises and open circuit and/or the second impedancecomprises an open circuit.
 18. The method of claim 12, wherein theimplanted signal processor is programmed with a signal processortransfer function such that the signal processor outputs a stimulationsignal based on an input signal received from an input source and thetransfer function.
 19. The method of claim 18, further comprisingupdating the signal processor transfer function based on the receivedfirst signal.
 20. A method of providing a communication signal andelectrical power from an implanted battery and/or communication moduleof a cochlear implant system to an implanted signal processorcomprising: generating a first signal via a signal generator within theimplanted battery and/or communication module; inverting the generatedfirst signal via a first inverter to produce an inverted first signal;outputting the generated first signal and the inverted first signal to afirst lead via one or more first capacitive connections; receiving, viathe one or more first capacitive connections, the generated first signaland the inverted first signal at the implanted signal processor;rectifying one or both of the received generated first signal and thereceived inverted first signal to generate a substantially DC outputsignal; and generating a second signal different from the first signalwithin the implanted battery and/or communication module; inverting thegenerated second signal via a second inverter to produce an invertedsecond signal; outputting the generated second signal and the invertedsecond signal to a second lead via one or more second capacitiveconnections; receiving, via the one or more second capacitiveconnections, the generated second signal and the inverted second signalat the implanted signal processor; and extracting data from the receivedsecond signal.
 21. The method of claim 20, wherein the first signal issubstantially an AC signal.
 22. The method of claim 20, furthercomprising analyzing the substantially DC output signal, and if thesubstantially DC output signal is insufficient to provide a stimulationsignal, increasing the electrical power provided to the signalgenerator.
 23. The method of claim 20, wherein the cochlear implantsystem further includes an implanted cochlear electrode, the methodfurther comprising providing a first impedance between the cochlearelectrode and the implanted signal processor and providing a secondimpedance between the cochlear electrode and the implanted batteryand/or communication module.
 24. The method of claim 20, wherein thefirst signal is a digital signal having a first clocking rate and thesecond signal is a digital signal having a second clocking rate, andwherein the second clocking rate is at least one order of magnitudehigher than the first clocking rate.